diff --git a/src/main/java/com/lambdaworks/redis/AbstractRedisAsyncCommands.java b/src/main/java/com/lambdaworks/redis/AbstractRedisAsyncCommands.java
index f311727681..1d513e18ed 100644
--- a/src/main/java/com/lambdaworks/redis/AbstractRedisAsyncCommands.java
+++ b/src/main/java/com/lambdaworks/redis/AbstractRedisAsyncCommands.java
@@ -817,7 +817,7 @@ public RedisFuture<String> set(K key, V value) {
     }
 
     @Override
-    public RedisFuture<V> set(K key, V value, SetArgs setArgs) {
+    public RedisFuture<String> set(K key, V value, SetArgs setArgs) {
         return dispatch(commandBuilder.set(key, value, setArgs));
     }
 
diff --git a/src/main/java/com/lambdaworks/redis/AbstractRedisReactiveCommands.java b/src/main/java/com/lambdaworks/redis/AbstractRedisReactiveCommands.java
index f3dd64bdc5..40289a44a4 100644
--- a/src/main/java/com/lambdaworks/redis/AbstractRedisReactiveCommands.java
+++ b/src/main/java/com/lambdaworks/redis/AbstractRedisReactiveCommands.java
@@ -801,7 +801,7 @@ public Observable<String> set(K key, V value) {
     }
 
     @Override
-    public Observable<V> set(K key, V value, SetArgs setArgs) {
+    public Observable<String> set(K key, V value, SetArgs setArgs) {
         return createObservable(() -> commandBuilder.set(key, value, setArgs));
     }
 
diff --git a/src/main/java/com/lambdaworks/redis/RedisCommandBuilder.java b/src/main/java/com/lambdaworks/redis/RedisCommandBuilder.java
index 3ac6e5e46f..49c0bece74 100644
--- a/src/main/java/com/lambdaworks/redis/RedisCommandBuilder.java
+++ b/src/main/java/com/lambdaworks/redis/RedisCommandBuilder.java
@@ -804,10 +804,10 @@ public Command<K, V, String> set(K key, V value) {
         return createCommand(SET, new StatusOutput<K, V>(codec), key, value);
     }
 
-    public Command<K, V, V> set(K key, V value, SetArgs setArgs) {
+    public Command<K, V, String> set(K key, V value, SetArgs setArgs) {
         CommandArgs<K, V> args = new CommandArgs<K, V>(codec).addKey(key).addValue(value);
         setArgs.build(args);
-        return createCommand(SET, new ValueOutput<K, V>(codec), args);
+        return createCommand(SET, new StatusOutput<K, V>(codec), args);
     }
 
     public Command<K, V, Long> setbit(K key, long offset, int value) {
diff --git a/src/main/java/com/lambdaworks/redis/RedisStringsAsyncConnection.java b/src/main/java/com/lambdaworks/redis/RedisStringsAsyncConnection.java
index 80cbbe03f8..575f5e87cb 100644
--- a/src/main/java/com/lambdaworks/redis/RedisStringsAsyncConnection.java
+++ b/src/main/java/com/lambdaworks/redis/RedisStringsAsyncConnection.java
@@ -273,7 +273,7 @@ public interface RedisStringsAsyncConnection<K, V> {
      * 
      * @return RedisFuture&lt;V&gt; simple-string-reply {@code OK} if {@code SET} was executed correctly.
      */
-    RedisFuture<V> set(K key, V value, SetArgs setArgs);
+    RedisFuture<String> set(K key, V value, SetArgs setArgs);
 
     /**
      * Sets or clears the bit at offset in the string value stored at key.
diff --git a/src/main/java/com/lambdaworks/redis/RedisStringsConnection.java b/src/main/java/com/lambdaworks/redis/RedisStringsConnection.java
index 7b11ccb906..631c53936c 100644
--- a/src/main/java/com/lambdaworks/redis/RedisStringsConnection.java
+++ b/src/main/java/com/lambdaworks/redis/RedisStringsConnection.java
@@ -267,9 +267,9 @@ public interface RedisStringsConnection<K, V> {
      * @param value the value
      * @param setArgs the setArgs
      * 
-     * @return V simple-string-reply {@code OK} if {@code SET} was executed correctly.
+     * @return String simple-string-reply {@code OK} if {@code SET} was executed correctly.
      */
-    V set(K key, V value, SetArgs setArgs);
+    String set(K key, V value, SetArgs setArgs);
 
     /**
      * Sets or clears the bit at offset in the string value stored at key.
diff --git a/src/main/java/com/lambdaworks/redis/api/async/RedisStringAsyncCommands.java b/src/main/java/com/lambdaworks/redis/api/async/RedisStringAsyncCommands.java
index 065a844684..645a7e47c4 100644
--- a/src/main/java/com/lambdaworks/redis/api/async/RedisStringAsyncCommands.java
+++ b/src/main/java/com/lambdaworks/redis/api/async/RedisStringAsyncCommands.java
@@ -267,9 +267,9 @@ public interface RedisStringAsyncCommands<K, V> {
      * @param value the value
      * @param setArgs the setArgs
      * 
-     * @return V simple-string-reply {@code OK} if {@code SET} was executed correctly.
+     * @return String simple-string-reply {@code OK} if {@code SET} was executed correctly.
      */
-    RedisFuture<V> set(K key, V value, SetArgs setArgs);
+    RedisFuture<String> set(K key, V value, SetArgs setArgs);
 
     /**
      * Sets or clears the bit at offset in the string value stored at key.
diff --git a/src/main/java/com/lambdaworks/redis/api/rx/RedisStringReactiveCommands.java b/src/main/java/com/lambdaworks/redis/api/rx/RedisStringReactiveCommands.java
index 9b78f1f18b..43749f4f64 100644
--- a/src/main/java/com/lambdaworks/redis/api/rx/RedisStringReactiveCommands.java
+++ b/src/main/java/com/lambdaworks/redis/api/rx/RedisStringReactiveCommands.java
@@ -267,9 +267,9 @@ public interface RedisStringReactiveCommands<K, V> {
      * @param value the value
      * @param setArgs the setArgs
      * 
-     * @return V simple-string-reply {@code OK} if {@code SET} was executed correctly.
+     * @return String simple-string-reply {@code OK} if {@code SET} was executed correctly.
      */
-    Observable<V> set(K key, V value, SetArgs setArgs);
+    Observable<String> set(K key, V value, SetArgs setArgs);
 
     /**
      * Sets or clears the bit at offset in the string value stored at key.
diff --git a/src/main/java/com/lambdaworks/redis/api/sync/RedisStringCommands.java b/src/main/java/com/lambdaworks/redis/api/sync/RedisStringCommands.java
index 76c80b95c7..dc2b7ae81a 100644
--- a/src/main/java/com/lambdaworks/redis/api/sync/RedisStringCommands.java
+++ b/src/main/java/com/lambdaworks/redis/api/sync/RedisStringCommands.java
@@ -266,9 +266,9 @@ public interface RedisStringCommands<K, V> {
      * @param value the value
      * @param setArgs the setArgs
      * 
-     * @return V simple-string-reply {@code OK} if {@code SET} was executed correctly.
+     * @return String simple-string-reply {@code OK} if {@code SET} was executed correctly.
      */
-    V set(K key, V value, SetArgs setArgs);
+    String set(K key, V value, SetArgs setArgs);
 
     /**
      * Sets or clears the bit at offset in the string value stored at key.
diff --git a/src/main/java/com/lambdaworks/redis/cluster/api/async/NodeSelectionStringAsyncCommands.java b/src/main/java/com/lambdaworks/redis/cluster/api/async/NodeSelectionStringAsyncCommands.java
index 76ba8ea57b..1fd013bcc4 100644
--- a/src/main/java/com/lambdaworks/redis/cluster/api/async/NodeSelectionStringAsyncCommands.java
+++ b/src/main/java/com/lambdaworks/redis/cluster/api/async/NodeSelectionStringAsyncCommands.java
@@ -267,9 +267,9 @@ public interface NodeSelectionStringAsyncCommands<K, V> {
      * @param value the value
      * @param setArgs the setArgs
      * 
-     * @return V simple-string-reply {@code OK} if {@code SET} was executed correctly.
+     * @return String simple-string-reply {@code OK} if {@code SET} was executed correctly.
      */
-    AsyncExecutions<V> set(K key, V value, SetArgs setArgs);
+    AsyncExecutions<String> set(K key, V value, SetArgs setArgs);
 
     /**
      * Sets or clears the bit at offset in the string value stored at key.
diff --git a/src/main/java/com/lambdaworks/redis/cluster/api/sync/NodeSelectionStringCommands.java b/src/main/java/com/lambdaworks/redis/cluster/api/sync/NodeSelectionStringCommands.java
index a662c7abe9..77221490f8 100644
--- a/src/main/java/com/lambdaworks/redis/cluster/api/sync/NodeSelectionStringCommands.java
+++ b/src/main/java/com/lambdaworks/redis/cluster/api/sync/NodeSelectionStringCommands.java
@@ -266,9 +266,9 @@ public interface NodeSelectionStringCommands<K, V> {
      * @param value the value
      * @param setArgs the setArgs
      * 
-     * @return V simple-string-reply {@code OK} if {@code SET} was executed correctly.
+     * @return String simple-string-reply {@code OK} if {@code SET} was executed correctly.
      */
-    Executions<V> set(K key, V value, SetArgs setArgs);
+    Executions<String> set(K key, V value, SetArgs setArgs);
 
     /**
      * Sets or clears the bit at offset in the string value stored at key.
diff --git a/src/main/java/com/lambdaworks/redis/output/CommandOutput.java b/src/main/java/com/lambdaworks/redis/output/CommandOutput.java
index 565dc2ef4b..265448c73c 100644
--- a/src/main/java/com/lambdaworks/redis/output/CommandOutput.java
+++ b/src/main/java/com/lambdaworks/redis/output/CommandOutput.java
@@ -110,6 +110,10 @@ public void complete(int depth) {
     }
 
     protected String decodeAscii(ByteBuffer bytes) {
+        if(bytes == null) {
+            return null;
+        }
+
         char[] chars = new char[bytes.remaining()];
         for (int i = 0; i < chars.length; i++) {
             chars[i] = (char) bytes.get();
diff --git a/src/main/templates/com/lambdaworks/redis/api/RedisStringCommands.java b/src/main/templates/com/lambdaworks/redis/api/RedisStringCommands.java
index 016c509a8a..a6837aab09 100644
--- a/src/main/templates/com/lambdaworks/redis/api/RedisStringCommands.java
+++ b/src/main/templates/com/lambdaworks/redis/api/RedisStringCommands.java
@@ -265,9 +265,9 @@ public interface RedisStringCommands<K, V> {
      * @param value the value
      * @param setArgs the setArgs
      * 
-     * @return V simple-string-reply {@code OK} if {@code SET} was executed correctly.
+     * @return String simple-string-reply {@code OK} if {@code SET} was executed correctly.
      */
-    V set(K key, V value, SetArgs setArgs);
+    String set(K key, V value, SetArgs setArgs);
 
     /**
      * Sets or clears the bit at offset in the string value stored at key.
diff --git a/src/test/java/com/lambdaworks/redis/CustomCodecTest.java b/src/test/java/com/lambdaworks/redis/CustomCodecTest.java
index 7c900d3cf3..31c5284a10 100644
--- a/src/test/java/com/lambdaworks/redis/CustomCodecTest.java
+++ b/src/test/java/com/lambdaworks/redis/CustomCodecTest.java
@@ -12,26 +12,46 @@
 import java.nio.ByteBuffer;
 import java.nio.charset.Charset;
 import java.util.List;
+import java.util.concurrent.TimeUnit;
 
+import com.lambdaworks.redis.api.StatefulRedisConnection;
 import com.lambdaworks.redis.api.sync.RedisCommands;
-import com.lambdaworks.redis.protocol.RedisCommand;
 import org.junit.Test;
 
 import com.lambdaworks.redis.codec.ByteArrayCodec;
 import com.lambdaworks.redis.codec.CompressionCodec;
 import com.lambdaworks.redis.codec.RedisCodec;
+import rx.observers.TestSubscriber;
 
 public class CustomCodecTest extends AbstractRedisClientTest {
 
     @Test
-    public void test() throws Exception {
+    public void testJavaSerializer() throws Exception {
+        StatefulRedisConnection<String, Object> redisConnection = client.connect(new SerializedObjectCodec());
+        RedisCommands<String, Object> sync = redisConnection.sync();
+        List<String> list = list("one", "two");
+        sync.set(key, list);
+
+        assertThat(sync.get(key)).isEqualTo(list);
+        assertThat(sync.set(key, list)).isEqualTo("OK");
+        assertThat(sync.set(key, list, SetArgs.Builder.ex(1))).isEqualTo("OK");
 
-        RedisCommands<String, Object> connection = client.connect(new SerializedObjectCodec()).sync();
+        redisConnection.close();
+    }
+
+    @Test
+    public void testJavaSerializerRx() throws Exception {
+        StatefulRedisConnection<String, Object> redisConnection = client.connect(new SerializedObjectCodec());
         List<String> list = list("one", "two");
-        connection.set(key, list);
-        assertThat(connection.get(key)).isEqualTo(list);
 
-        connection.close();
+        TestSubscriber<String> subscriber = TestSubscriber.create();
+
+        redisConnection.reactive().set(key, list, SetArgs.Builder.ex(1)).subscribe(subscriber);
+        subscriber.awaitTerminalEvent(1, TimeUnit.SECONDS);
+        subscriber.assertCompleted();
+        subscriber.assertValue("OK");
+
+        redisConnection.close();
     }
 
     @Test