I'm not even close to being an expert on the AR platform rifles, but I can tell you this. Aside from the manufacturer, know what model you want. For example, do you want a carbine barrel length, a fixed or detachable handle? The detachable handle has more options to experiment with to your personal liking. From the barrel twists to the add-ons (furniture) you can get overwhelmed. From research I've seen, the top dogs in the AR field are (in no particular order): Colt, BCM, Daniel Defense, Noveske, Les Baer, Rock River, LMT, and probably a few more. The price tags will scare you. Good luck
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