I have gotten (1) X-Caliber Remage, carbon fiber, pre-fit in 6.8 Western, and (2) CarbonSix shouldered Remington 700 prefits in 6.5 PRC and 7 SAUM. As someone mentioned earlier, McGowan does the blanks for CarbonSix. All three shoot very well. I trued all three actions concentric to the bolt raceway and left the threads the standard size, just touched them up a little. The only strange thing I noticed is the 6.8W seems to be throated short, or something else is going on. I never seemed to be able to get a load with a COL over 2.85" with any .277 bullet combo. I asked them about it and they gave me a standard answer, "we used a SAAMI spec reamer, yada, yada, yada. COL is not a determining factor in handloads, your jump or jamb is." While I agree, I still find it strange that a cartridge that is supposed to have a COL up 2.95" for the 175 Sierras is a whole 0.1" shorter with just a 0.01" or so off the lands. The whole thing just never added up to me. I also used a REM 721 action, maybe that played into it as I saw something interesting later in a CarbonSix on a 722. I ended up letting the issue go as it shot well and continues to shoot well to this day. In the end I prefer the shouldered pre-fit look a lot better than the Remage. However the Remage was plug and play. I had to adjust headspace a tad for the 6.5 PRC CarbonSix pre-fit, it was a hair snug. As for the 7 SAUM, I used a REM 722 action and I had to adjust quite a bit to get proper headspace for it. I chalked it up to being a 722 and not a 700, or I also used Mack Brothers bolts and one bolt seemed to have larger lugs than the other. No matter I solved the problem. Most people would likely just go to a gunsmith and have professional take care of it. I am not most people and I have very few gunsmiths in my area and none are accepting work these days. So I learn to do all my own work. Both CarbonSix's shoot a bit better than the X-Caliber. But nothing to complain about. In the end I think X-Caliber and McGowan both make fine barrels. You should be in good hands with either.