Received my RMA upper with the new sled and CH. So much better, way more material on the bottom side of the sled and the cutout for the CH is perfect to were it pretty much drops into place ( right or left side with ease no more fighting or having to jam it in). Racking the bolt is much smoother as the CH/sled is no longer rubbing the inside channel. Excellent Job PSA, for taking the feedback from a small number of us and correcting this issue and improving the quality.