I have a long action AXMC and use it for matches, hunting, and just about everything else. It works great in short action mode and is very reliable. I shoot 6XC, 264 win mag, and the 300 Norma. I would suggest not using cases with small rifle primers, unless you get all your bolts bushed odds are you will have issues. All my barrels were spun up by TS Customs in Miller, SD and they all shoot beyond my expectations. You can get his barrels from Dominic at Brotherhood Arms in Watertown, SD. He usually has most of the popular barrels configurations on hand and ready to ship. If you like the ergonomics of the AI chassis and are OK with a heavy rifle you will not regret it. By the way that 264 win mag barrel was suggested by Travis Stevens at TS Customs and it's becoming my favorite barrel (140 hybrids at 3150 fps in a very mild load). Tons of performance with acceptable recoil. Don't even bother with the 6.5 prc or the 6.5 Saul, you have a long action and you might as well use it.
Good luck with your decision.....