nordic, evo, and krinker are probably the big 3 right now... Nordic allows you to stick AR15 parts (stock, grip, handguard etc...) on for an even bigger selection of options. I'll be putting the finishing touches on mine in the next 2 days. I'll get some pics, and a range report up soon. If you're in the same part of eastern ON as me, maybe I can show you in person.