Well, out of those barrels I'd get a Freak Jr because it comes with inserts (4 of em right?) so that you can match the paint to the barrel, therefore getting greater accuracy. That's a nice gun too, although you COULD (if you had the money) upgrade the hopper to maybe an Egg, just for the faster feed rate.
Progressive and Teardrop are the same.. The Teardrop just looks a bit different.
All barrels perform essntially the same, provided you have a good paint to barrel match. That means you drop a paintball int he abrrel...it stops, but you can easily blow it out. That is a good match... If you turn blue trying to blow it out, it's too big. If it falls straight through, your paint is too small.
Im not upgradeing my hoper (i just got the revvy yesterday) until i get a gun that can outshoot the revvy,with my gun now I can probly make it up to around 14 bps but that would be rare, especially in a game, to just go all out with no degree of accuracy. It probly wont outshoot the revvy anyway with a very short 14 bps burst. And for some reason right now i want to collect all the guns I get and have them seperate with own tank and hoper and all the upgrades I do to them, so a revvy is a good hooper for this gun if im not going to move the hoper to a faster gun later
OH and with a barrel kit do you have -Back with Tip and Insert- or Back with Tip OR Insert and in what order to you screw them together.