I wouldn't want a "heavy" barrel personally.
Yep, I've got (2) completel AR's (well, at least the rest of the parts for the second one are in the mail or at my house)... my match/varmant rifle, which is a J&T 24" bull barrel kit rifle (1:8, stainless .910 barrel, flat top, floated barrel, pic. rail gas block, etc)... With the extra 3# in the stock, I've not weighed it, but it's got to be close to 15#... MUCH heavier than my Garand... This is a target/accuracy rig, that I WOULD NOT want to carry around for any length of time...
My new rifle is a CMMG Gov. profile midlength 16" barrel'd upper W/ BCG, 1:7, chrome lining, M4 ramps, flat top, etc. for $525 (because none of the kit companies make a gov't profile middy), with a Mega lower and 6-position stock... Paying right at $100 more for it than for the Del-Ton kit with M4 ramps and chrome lining, but I hear it's a better upper, it's 1:7 (same 75gr. accurate loads as my 24" I suspect), and it's a lightweight barrel....
I figured I wanted to have something for accuracy that I did't have to carry around much, and one for plinking (if you can afford to plink any more), a .22LR conversion plinking, carbine/e-gun matches, and heaven forbid, more "social occasions" should there be a disaster of some kind (Katrina ring a bell?)...
Mike