I recently bought a Rock River Arms stripped lower on the thought of building an AR varmit rifle. Any thoughts or experience with who's upper kit I should purchase to finish up the project. I wish to shoot light bullet 50-60 grain. I am seeking the best accuraccy for the buck. Several companies make complete kits less stripped lowers, they are where my intrest really lies. Kits I have looked at are: model one, uses shaw barrels, olympic arms a little higher in price is it worth it, rock river arms, I believe they sell wilson barrles. I am in no hurry to build but plan on maybe trying to buy/ build at tax return time. Very interested in results some of you folks might have had with these kits. Would consider other kits. My hope and need is to keep the upper kits in the 500.00 price range. Will only consider flat top and 20" barrel. Twist rate of maybe 1-10, not sure on that. Have had several give opinions on that topic. PLease help me if you can. I am an avid reader here, enjoy the comedy and the advice this diverse group offers up but rarely post. Never owned a black gun so if I seem a little ignorant on the topic its because well I am. Thanks Sharps-Nut