Meh. It's nothing special. There seems to be a high lemon rate but if you can get past that (ie. not get a lemon) they're decent for what you're paying for. Otherwise it's just a moneypit.
Also, they're popular for people who want to basically build a gun from the ground up or aspiring gundocs. Reason being is that it's basically a $150 "3D instruction manual" and you'll get pretty good repairing/upgrading the internals.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE