Any will do. I have all five different backs so I can use most paint. I have found that PMI/RPS paintballs are probably the best. PMI Premium and EVIL are the best I have used.
Great Barrel. I have the complete set so i have 5 backs and 4 fronts. It is great for when i play different types of games and positions. I can always match paint no matter where i go to play. If i want to do some long ball shooting i have the 14 and 16 inch tips, playing up front i have the 10 and 12 inch fronts. It is a great all around barrel. I got it used so i did not have to pay to much for it.
Nothing bad so far. Great all around barrel. Only competition is the Freak, except the Freak is a lil pricey when you consider what you get when u get a CP kit.
Great barrel, I highly recommend it. Buy one today.