I have two AR10 "mutts" or "mongrels" uppers. One in .308WIN, and one in 6.5CM. Put them together from a hodge-podge of parts, but they are good enough for steel target shooting. 960 yards for the 6.5CM, and 800 for the .308. Both have heavy barrels, and thus, I can shoot long strings of fire. Both of them share a PSA lower, with a two-stage 4.5LBS drop-in trigger, an a PRS stock. With optics, they top the scale at or around 12 Lbs. They are dual purpose: I get to shoot, and at the end of the range session, I feel like I have been lifting free weights!
I do shoot my buddies SCARs, and I do like the rifle, but the price!
My mutts and all of their parts are less expensive than the SCAR, without optics, cool bipod, and the rest of the bells and whistles.
IF I were to purchase a production rifle, it would be the SCAR, even with their reciprocating charging handle.