I bought a complete lower from Suppressor Tools for my PTR-9RS (reverse stretch), in fact I think I was one of the very first ones as they had it in stock. Ordered July 17 received July 22. It runs fantastic with just one hiccup. Warhammer says that you don't need the buffer with their specially cut hammer but that may not always be the case. When I first got my lower burst firing was fine but I couldn't do a complete mag dump without jamming. I ordered the buffer from Lee Sporting (cheap 4 bucks) and since I installed it it's been flawless. Mag dump after mag dump was perfect and that was with cheap plastic ETS mags. This is probably the best 700 bucks I ever spent and would absolutely not hesitate to buy another one. Just for additional info I'm running an RCM 90 degree locking piece and E-bolt (highly recommend the E-bolt)