Yea Colorado does allow FA's, I see em' at the range not too infrequently. Once you're approved and pay the 200 tax fee thing, its just like any other gun, take and shoot it anywhere you please thats acceptable to shoot any other arm.
I think a better question would be; what are FA's good for? In a practical senario, not just showing off or having fun, or collectability. Am I missing something or is there a real tacticle niche for them?
I priced a FA MP5 at around 4000. here locally.
For a 9mm