who has used Adam Arms for high quality AR-15 (,223/5,56) BCG and Piston components??

I put a few thousand rounds on one of their add on kits. I think the timing was a little faster due to the mechanical linkage. My brass was alway a little dirtier and the pop from the ejection port seemed louder than with my rifle length gas DI guns. i sold it and moved to a tube and adjustable gas block.