My Overwatch PolyDAT for my Gen 5 19 showed up in the mail today. I was anticipating having to modify it for it to work with my "standard trigger" gadget like Tom mentioned, but it works fine as is and the gadget lays flat. This is a pleasant surprise since my previous experience with one of their metal triggers wouldn't allow the gadget to lay flat.
The PolyDAT may have removed a very very small amount of take up, but since the gadget functionality isn't impeded, I'm not going to mess with modifying it. I'm VERY happy with the feel of the trigger and see absolutely no reason to pay extra for a metal version. I'd actually say the trigger pull on this feels better than the metal version I had before. I've got more on the way for my other 19 and my 48.