Looking to add an AR to my collection and, shooting USPSA production, thought I may as well make it a potential 3-gun, just in case. Any thoughts? I'm really leaning toward the M153GN18, although I know 16s are in vogue. They have a great 13" that's pinned and welded compensator to 16" but I feel that would limit my future options. Thoughts? We're looking at the $1400ish range.