I don't own any .308 AR's but have been seriously considering buying one.
I've been leaning toward the Rock River 20" barrel flat-top. I think the main thing the RR has going for it is that it uses FAL mags. I've already got an Entreprise STG-58 FAL-type rifle and I've got a butt-ton of mags for it, so that helps with supply problems.
All the other AR-10-type rifles use proprietary mags that are quite pricey compared to FAL mags. I know there are aftermarket mags available for the DPMS, but they've not been around long enough yet to gain my trust as to their reliability. I know Pro-Mag is making some, but I've had a lot of issues with Pro-Mags in the past. They make great AR-15 mags, but their Mini-14 mags are for sh*t. They were also the ones who introduced those large capacity drum-type mags for the 1911 which reportedly won't feed reliably for more than 2 or 3 rounds at a time. I know every site I've gone to that sells gun accessories have always had those 1911 drums on clearance sale, apparently to put shed of them - Midway, Grafs, Natchez, Bass Pro, etc.
JMHO......
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