need new rear shock with CLASS

[dn14004]

I replaced the front springs with progressives and now need to do something with the rear. I ride very aggressively and now the rear end wallows. I don't want to have to remove the class [it's all the class i have left] like I did on the front. after reading some of the other threads I see that I can replace just the spring since there are no air or fluid leaks is the shock rebuildable? how does the remote dampening work is there anything there that needs maintenance? Am I just being stubborn about keeping the air? There's no way I'm going to adjust the progressive with a spanner more than 1x a year is the loss of adjustability going to make a big differance between single\double baggage\empty. ride quality is important but handling is first. THANX:Venture: