If you are going to leave the motors stock then yes the prop and shaft upgrade is good and yes you can run 14 cells just make sure you put in some water cooling for the motors. I put in two Trinity Monster Maxx Wild motors on 14 cells and the upgrade prop and shaft from offshore and I had heat problems on the motors, I believe the upgrade props were too much for the 540 size motors, they don't have as much torque as the 550 motors. I also had water cooling jackets on from offshore and they are much better a cooling than a regular coil cooling system.

What more modified version of the aqujet are you talking about? Is it going to be better than the Aquajet Extreme from offshore? Is it offshore that is doing this new upgrade?