diff --git a/src/emucore/OSystem.cxx b/src/emucore/OSystem.cxx
index d0e835816..3259f5fae 100644
--- a/src/emucore/OSystem.cxx
+++ b/src/emucore/OSystem.cxx
@@ -177,6 +177,9 @@ void OSystem::saveConfig()
 
   if(mySettings)
     mySettings->saveConfig();
+
+  if(myPropSet)
+    myPropSet->save(myPropertiesFile);
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
diff --git a/src/emucore/Props.cxx b/src/emucore/Props.cxx
index 710f62003..20631f5e2 100644
--- a/src/emucore/Props.cxx
+++ b/src/emucore/Props.cxx
@@ -195,6 +195,22 @@ void Properties::writeQuotedString(ostream& out, const string& s)
   out.put('"');
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool Properties::operator == (const Properties& properties) const
+{
+  for(int i = 0; i < LastPropType; ++i)
+    if(myProperties[i] != properties.myProperties[i])
+      return false;
+
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool Properties::operator != (const Properties& properties) const
+{
+  return !(*this == properties);
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 Properties& Properties::operator = (const Properties& properties)
 {
diff --git a/src/emucore/Props.hxx b/src/emucore/Props.hxx
index 9a6c9a874..c07981df4 100644
--- a/src/emucore/Props.hxx
+++ b/src/emucore/Props.hxx
@@ -122,7 +122,15 @@ class Properties
     */
     void setDefaults();
 
-  public:
+    /**
+      Overloaded equality operator(s)
+
+      @param properties The properties object to compare to
+      @return True if the properties are equal, else false
+    */
+    bool operator == (const Properties& properties) const;
+    bool operator != (const Properties& properties) const;
+
     /**
       Overloaded assignment operator
 
diff --git a/src/emucore/PropsSet.cxx b/src/emucore/PropsSet.cxx
index 16cd88a34..826806a4e 100644
--- a/src/emucore/PropsSet.cxx
+++ b/src/emucore/PropsSet.cxx
@@ -39,21 +39,9 @@ void PropertiesSet::load(const string& filename)
 {
   ifstream in(filename);
 
-  // Loop reading properties
-  for(;;)
-  {
-    // Make sure the stream is still good or we're done 
-    if(!in)
-      break;
-
-    // Get the property list associated with this profile
-    Properties prop;
-    in >> prop;
-
-    // If the stream is still good then insert the properties
-    if(in)
-      insert(prop);
-  }
+  Properties prop;
+  while(in >> prop)
+    insert(prop);
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
@@ -165,10 +153,20 @@ void PropertiesSet::insert(const Properties& properties, bool save)
   if(md5 == "")
     return;
 
+  // Make sure the exact entry isn't already in any list
+  Properties defaultProps;
+  if(getMD5(md5, defaultProps, false) && defaultProps == properties)
+    return;
+  else if(getMD5(md5, defaultProps, true) && defaultProps == properties)
+  {
+    myExternalProps.erase(md5);
+    return;
+  }
+
   // The status of 'save' determines which list to save to
   PropsList& list = save ? myExternalProps : myTempProps;
 
-  auto ret = list.insert(make_pair(md5, properties));
+  auto ret = list.emplace(md5, properties);
   if(ret.second == false)
   {
     // Remove old item and insert again