Nelson Anarchy, Nel-Splat, Karnage Tear, Worr Perfection, Monster (admit it, everyone's used it once - but then never again!)
'05 Prostock, E2'd w/ Zero B 1.2, Edge Bolt and Miniblock, Belsales Ram with QEV's, 04 Macdev Regulator, Sonic LPR, Legionair 68/45 blah blah blah. Oh, Evil Pipe kit too.
Whatever works for you, I'd recommend nothing longer than 14". 12" would probably be better, .689 if it's cold .692 if it's hot.
Fill is thick.
Dull Fill - Yellow mustard is brighter
Distorts when hot @>85 deg
The first thing I'd like to say is that I'm paranoid about keeping paint right around 75 degrees. I keep it all in a nice cool spot in a closet that doesn't get any hotter than that, ever. Using the default setting for the B2 I couldn't get more than one ball in a dozen to come out unbroken. Changed the speed down to 2/6 and that problem was solved. While this was going on I found that balls were breaking just before they left the barrel (@280 fps). I then had to reduce the cocking pressure and thus overall speed to around 8bps in order to shoot on a regular basis, with a .689 barrel. The day of play the paint grew substantially because of the high tempratures and nothing less than a .692 barrel would work. Even then, just running around I found broken balls in my pods, and probably dumped close to 600 over the course of a day, where I only shot around 1500 (mainly as a result of constant barrel cleaning).
I honestly don't feel like it should be this much work to shoot a paintball. Of the two cases I bought, only about half actually were shot at fellow paintballers. It also can't be used with high rates of fire (it's not hard to pull more than 8bps in a game) which is kind of a downer. In cooler weather, better results may be obtained as the shell would be slightly stronger. If you can get them out of your barrel they're a great ball, but it's a lot of work to get to that.