I have the DPMS A3 Lite, and absolutely love it. Have put around 1000 rounds through without any problems whatsoever. The mags that come with the rifle feel "cheap" but work fine, picked up several PMags and they work fine as well. Accuracy is decent, pretty much all I shoot is cheaper brass cased 55gr FMJ and I can hold 3-1/2" groups at 200 yards with just a cheap scope. I'm sure with a good scope and some match grade ammo, those groups could tighten up a fair bit.
Several years ago I had an Olympic Arms Plinker, never gave me any problems either, think you would be good to go with either one.