Plus the grip safety on the 1911. I really like the idea of that.
That's a good feature for a dropped firearm, with the thumb safety off - but when holstering, which is what (I think) causes many of the Glock and DA revolver "shoot yourself" incidents (no finger needed in the trigger guard), one is apt to be depressing the grip safety. In order to be safe against the holster entering the trigger guard, one depends on the habit of cycling the thumb safety to ON before holstering.
Or, looking at the habit from the other direction, the only time the thumb safety goes to OFF is just before opening fire. Part of the activity of gripping should be placing the thumb firmly aside the slide, above the thumb safety.