First off, welcome to the forum cowboy.
What are you trying to do with this rifle, what ranges are you trying to shoot? That is going help people here answer your questions from their experience. Because as others have said, there is a pretty big difference in setup between the two types of guns you are looking at. Weight accumulates quickly in these guns and many people forget to add that the ammo is nearly 3 times heavier compared to an ar15. I have changed around the LMT MWS quite a bit and its not really modular in the sense you want to be constantly moving parts around in the field although you can. Not to mention having to check your return to zero constantly on a precision rifle because you're moving barrels and scopes around is not something I can put up with (and I have done it).
At the very least to do what you're interested in you will likely want 2 optics. A 5-25x scope is really not practical for any shooting done off hand. Which means now you are likely adding a bipod (more weight). The LMT with 13.5 inch LW barrel and an Eotech is pretty dope and actually light enough that I would take it to hunt hogs.
How much are you realistically looking to spend and when are you looking to have the gun in hand by? It is not a great time to be buying the LMT rifles and many others right now and most are going for highly inflated prices, with barrels being very difficult to source. However, if you are willing to pay the premium they do exist. I bought mine a year ago from a guy in Austin thinning his collection, buying these used is likely the way to go. Most people talk big about shooting bajillions of rounds but its all talk.
Think hard about what you want to accomplish with this rifle, it'll save you tons of money.
And because no thread is complete without pics...
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