I bought a SW performance Center 9L 5" for USPSA competition in the open class and I bought a Smith & Wesson 9 CORE 5" for conceal carry. I'm one of those guys who shoot a lot and I do a lot of practice on technique and shooting skills. When I first got my performance center I was very unhappy with the accuracy I was getting so I bought one of Randy's threaded apex barrels gunsmith fitted and I couldn't believe at the results I was getting at 25 yards, I can eat the center out of a target now, my friends that have high $ 1911's cannot believe the accuracy I'm getting out of my SW. I have a lot of other parts install in it too from Randy but the barrel made a huge difference in accuracy.
Then I bought my 5" SW CORE for conceal carry, because I wanted to shoot a gun similar to my performance center. I was getting the same results for accuracy out of my core so I bought a apex non threaded barrel gun Smith fitted for it and got the same great results at 25 yards. Just from my experience Randy's barrels is money well spent.