Calling all 950/755/Definitive Technology owners...

As a new 950 owner I'm starting to wonder what a 755 will do for my current system in terms of sound improvements. Current set up includes:

950 Pre/Pro
Pioneer ELITE VSX-21 (85x5 for power only)
Panasonic RP91
Fronts = Def Tech BP2006TL's
Center = Def Tech CLR2300
Rears = Def Tech BPX's (just ordered them)

Can I expect huge differences if I mate my 950 with a 755 v.s. the current power my Pioneer receiver is providing?

Any and all comments on this subject are very much appreciated....