Guns, Dogs and Blades QnA

Buddy of mine just picked up one of the Walther .22lr M4 AR15's. Nice little rifle except for heavy trigger. All metal I think, whereas the S&W were mostly plastic. I gave him a scope to try out until he decides what he wants to put on it. The plastic flip up sights that came with it are for ****.
I want to get a dedicated .22 upper so I can run it with my NRA Match/XTC uppers. I run Geissele triggers on my ARs and customs on my Palma/1000yd bolt guns, and can NOT stand a crummy trigger. No excuse for it. Ruins everything.