diff --git a/AyCode.Core.Tests/Serialization/AcBinarySerializerCircularReferenceTests.cs b/AyCode.Core.Tests/Serialization/AcBinarySerializerCircularReferenceTests.cs
index be9b228..9497f38 100644
--- a/AyCode.Core.Tests/Serialization/AcBinarySerializerCircularReferenceTests.cs
+++ b/AyCode.Core.Tests/Serialization/AcBinarySerializerCircularReferenceTests.cs
@@ -19,7 +19,11 @@ public class AcBinarySerializerCircularReferenceTests
     /// - StockTakingItem has Product navigation property
     /// </summary>
     [TestMethod]
-    public void Deserialize_CircularReference_ParentChildBackReference()
+    [DataRow(true, true)]
+    [DataRow(false, true)]
+    [DataRow(true, false)]
+    [DataRow(false, false)]
+    public void Deserialize_CircularReference_ParentChildBackReference(bool useSgen, bool useMeta)
     {
         var parent = new CircularParent
         {
@@ -58,6 +62,10 @@ public class AcBinarySerializerCircularReferenceTests
 
         var option = AcBinarySerializerOptions.Default;
         option.ReferenceHandling = ReferenceHandlingMode.All;
+        option.UseGeneratedCode = useSgen;
+        option.UseMetadata = useMeta;
+
+        Console.WriteLine($"\n========== ReferenceHandling: {option.ReferenceHandling}, UseSgen: {option.UseGeneratedCode}, UseMeta: {option.UseMetadata} ==========");
 
         var binary = parent.ToBinary(option);
         var result = binary.BinaryTo<CircularParent>();
@@ -83,7 +91,11 @@ public class AcBinarySerializerCircularReferenceTests
     /// Test list of parents with circular references.
     /// </summary>
     [TestMethod]
-    public void Deserialize_ListOfCircularReferences_AllItemsCorrect()
+    [DataRow(true, true)]
+    [DataRow(false, true)]
+    [DataRow(true, false)]
+    [DataRow(false, false)]
+    public void Deserialize_ListOfCircularReferences_AllItemsCorrect(bool useSgen, bool useMeta)
     {
         var parents = Enumerable.Range(1, 5).Select(p =>
         {
@@ -132,6 +144,10 @@ public class AcBinarySerializerCircularReferenceTests
 
         var option = AcBinarySerializerOptions.Default;
         option.ReferenceHandling = ReferenceHandlingMode.All;
+        option.UseGeneratedCode = useSgen;
+        option.UseMetadata = useMeta;
+
+        Console.WriteLine($"\n========== ReferenceHandling: {option.ReferenceHandling}, UseSgen: {option.UseGeneratedCode}, UseMeta: {option.UseMetadata} ==========");
 
         var binary = parents.ToBinary(option);
         var result = binary.BinaryTo<List<CircularParent>>();
diff --git a/AyCode.Core.Tests/Serialization/AcBinarySerializerIIdReferenceTests.cs b/AyCode.Core.Tests/Serialization/AcBinarySerializerIIdReferenceTests.cs
index d3926d4..da2cdea 100644
--- a/AyCode.Core.Tests/Serialization/AcBinarySerializerIIdReferenceTests.cs
+++ b/AyCode.Core.Tests/Serialization/AcBinarySerializerIIdReferenceTests.cs
@@ -82,7 +82,11 @@ public class AcBinarySerializerIIdReferenceTests
     /// Tests all ReferenceHandling modes: None, OnlyId, All
     /// </summary>
     [TestMethod]
-    public void SameInstance_SerializeAndDeserialize()
+    [DataRow(true, true)]
+    [DataRow(false, true)]
+    [DataRow(true, false)]
+    [DataRow(false, false)]
+    public void SameInstance_SerializeAndDeserialize(bool useSgen, bool useMeta)
     {
         var modes = new[] 
         { 
@@ -93,8 +97,6 @@ public class AcBinarySerializerIIdReferenceTests
 
         foreach (var mode in modes)
         {
-            Console.WriteLine($"\n========== ReferenceHandling: {mode} ==========");
-            
             // Arrange: SAME instance used multiple times
             var userPreferences = new UserPreferences();
             var sharedTag = new SharedTag { Id = 1, Name = "ImportantTag", Color = "#FF0000" };
@@ -119,7 +121,13 @@ public class AcBinarySerializerIIdReferenceTests
 
             order.Items[1].ParentOrder = order;
 
-            var options = new AcBinarySerializerOptions { ReferenceHandling = mode };
+            var options = new AcBinarySerializerOptions
+            {
+                ReferenceHandling = mode,
+                UseGeneratedCode = useSgen
+            };
+
+            Console.WriteLine($"\n========== ReferenceHandling: {options.ReferenceHandling}, UseSgen: {options.UseGeneratedCode}, UseMeta: {options.UseMetadata} ==========");
 
             // Act
             var binary = AcBinarySerializer.Serialize(order, options);
diff --git a/AyCode.Core/Serializers/Binaries/AcBinarySerializerOptions.cs b/AyCode.Core/Serializers/Binaries/AcBinarySerializerOptions.cs
index 6b01f75..7d6d1a3 100644
--- a/AyCode.Core/Serializers/Binaries/AcBinarySerializerOptions.cs
+++ b/AyCode.Core/Serializers/Binaries/AcBinarySerializerOptions.cs
@@ -82,9 +82,9 @@ public sealed class AcBinarySerializerOptions : AcSerializerOptions
     /// allowing the deserializer to match properties by name between different types.
     /// Default: false (no overhead)
     /// </summary>
-    public bool UseMetadata { get; set; } = false;
+    public bool UseMetadata { get; set; } = true;
 
-    public bool UseGeneratedCode { get; set; } = true;
+    public bool UseGeneratedCode { get; set; } = false;
 
     /// <summary>
     /// Controls how string interning is applied during serialization.