I think youre going to be happy with it.
I picked up a M&P15T in a trade awhile back. Its a good shooter. You dont have to do anything special with it as far as breaking it in. Just load it up and have at it.
For practice/blasting, I basically just use my reloads. Other than that, commercial or GI.
I have an Aimpoint ML2 on a LaRue cantilever mount on mine.
Here's mine
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