I can set you at ease somewhat. Their cans are nice. It's true they aren't innovators anymore, but many of the better cans out there use similar technology to one another. The more innovative companies also tend to be the more gimmicky ones too (Sico is an exception). Innovation without proper testing first is what drove AAC under. FWIW, the SDN6's and 556SD's that I have fit 51T mounts, which are horrible, but the cans themselves work as well if not better than some others. The flash hiders "PING!" when fired, but you won't have this problem. The brakes don't do that.
CS sucks but IME it got better right after Remington took over. A mount that AAC screwed me over for 3 years was replaced no problem. Not sure how they are doing now, the xxT mounts all have similar problems and they know it, so they quit honoring their own warranty and quit accepting end cap strikes as reasonable warranty work. They tried everything they could to put the blame off on the owner, always insisting the rifle be sent back to have the threads checked (which often are off a bit). Anything to say there's reasonable doubt it was the mount.
They did include the 90T mount on the new sniper rifle Remington is selling the Army. I've heard the 90T actually isn't that bad, like 3rd time is a charm. What you want to do is keep the teeth clean and free from wear, especially excessive wear. When you put it on depress the latch and hold it down as you would when removing it --the more it ratchets, the more it wears those teeth down as well as the teeth on the latch. Don't let it rest on or hit rough or hard surfaces (for soldiers this is sometimes a problem). Hopefully since Army went with it they've got it worked out now. Because it'd be a shame and it'd be bullshit if you have do what I did, the following, in order to make it fit tight and hold decent groups:
If the can has wiggle when it goes on and it's close to engaging the next tooth on the mount, you can polish up the edges of the teeth and carefully polish the beveled portion of the mount that mates to the can. Remove enough material, usually not much, and it'll catch the next tooth and lock up TIGHT. This is what I had to do to a couple of 51T's and they fit tight now, but still ping. If they fit loose but barely move to the next tooth there isn't much you can do without putting it on a lathe or maybe a drill press and removing more material, or just living with it --it'll get better and fit tighter as it gets dirty.
The other option, the no-work option, is to order a handful of mounts (the more the better) and picking one that works and sending the rest back. Or if there's a local dealer that'll let you do that in the store, to find the "right one". I like to do this when I can. That's all I can say about that.
For .338LM I went with Elite Iron, same as with .50. They build solid cans for good prices. TBAC is another good one and probably the ideal choice. But you already bought this one so that's it, right? If so, don't worry, it's actually a very nice can and as long as it fits solid on the mount, you shouldn't have any issues you wouldn't normally have with any other can. And I bet the newer mount and the bigger can probably won't have as many problems as did the 51T SD's. Good luck!
