Their are 3 differences, the drive unit (propeller assembly), motor, and shroud. The motors are not incredibly different, the best way to look at the motors is they are like computer processors, the 2Ghz and 2.4 Ghz are from the same run, the 2.4Ghz ones just came out better. The 6095 motor blocks have a few extra hz (about 180 more rpms) and the shaft has to be more precisely centered because the drive unit uses a bigger magnet and the tolerances are much tighter. Basically, you could change the shroud and change the flow pattern, the flow will increase because it is less restrictive, but you will basically go from about 1450gph and a 4ft by 18" pattern to about 1750gph and a 30" cube pattern, I would not recommend the bigger propeller as it could be noisy and since the rpm will be lower, you wouldn't gain that much more.