I have held a thousand AR15/M16's in my lifetime, probably more. GM, Clot, Oly, DPMS, Stag, Mega, you name it.
I have never seen much difference, save cast/forged, felt much difference, save finishes, but that LMT complete rifle, I dont know what it is about that damn rifle, it just feels better than all the rest of them. Period.
I dont own an LMT, and have no plans to do any changing of my arrangement as of right now, but I do know, in my hands, to my senses, that damn thing LMT is building feels like the best complete AR15 I have ever held.
<shrug>