I bought the BKO just recently and it was great You might want to get a all american barrel with cocker threads and a freak front you also want to get the least trigger distance in the pull this maximizes your bps alot. I'd recomend a Halo b with rip drive or an egg evlution 2 will do. Make sure you don't use co2 with it only Nitrous. all in all the is a great gun but make sure you get a pds it makes a world of difference.

i got the gun for 300, and upgraded it with a freak barrel, right off, as i played, i realized it had some blow back issues, so i put in a shocktech bolt, i also put an aka sidewinder reg, you may feel it neccesarry to put in a vision system, but i did not, it feed great with and evvy2, or you could use a halo, but the egg is fine, this gun is great for the money, and easily upgradable, and easy to maintain