Colt and LMT are both top quality. I've shot an LMT, and it performed flawlessly. But so did the three Bushmasters I shot that day. LMT and Colt will hold their value the best, but then again, I'm not planning on selling my gun. I've got other things to sell first if it comes to that. My RRA functions just as good, and if on the off chance that something breaks (I'll probably be hit by a meteor first), I'll enjoy breaking my rifle down and fixing it. I'm not gonna pay $1200 for a rifle that does the same as my RRA. I saved that money and bought an ACOG with Docter. IMO, that's a better deal. A Stag will work fine, just break it down and look at the BCG to make sure it's staked right.
Unless you're using your rifle every day, you probably won't put enough wear and tear on it to break something that you can't fix very easily. Buy the Stag, don't drink anyones Kool-Aid (except the anti-Olympic Arms stuff), and enjoy two rifles for the price of another one.