As others said, buy what you really "love" not something to "settle on" as you will end up with two rifles
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It seems there are plenty of used SCAR 17s for around low 3K.
LMTs are much more difficult to get, and you will probably have to assemble it from complete lower and upper as I believe LMT is no longer selling complete MWS rifles.
You can also buy lightweight, short barrels for LMT, getting its weight closer to the SCAR.
I own both and prefer LMT MWS. It's a bit heavier than the plain SCAR, but there is something about AR's familiar manual of arms. Plus, I managed to smack my thumb twice on SCAR's charging handle (which is a non-issue now).
I also own Colt Le901. In the fantasy world, that would be my "go-to" .308 platform because it's an AR that's lighter/handier than MWS. Sadly, it's no longer made. It's equipped with a 1-4 LPVO.
If you really must, Aero precision seems to have a decent reputation for AR10 platform. The only anecdotal advice is to try and buy either a complete rifle or everything from the same maker to minimize potential issues.