[Serum]

The hvmaxx is nice, if you want a bit more than stock. the 9L/9920 combination is way more powerfull. the hvmaxx is running around 30-35 mph, and the 9L can be geared for mid 40's on 14 cells.

The 9L can take the maxximum available power from your batteries (batteries use to be the limmit in a setup, a setup can't be any stronger than the power the batteries can deliver)

The ghost stories of the sensorless setups cogging badly belongs to the past. Now a days, those sensorless setups run silky smooth, with neglectable cogging.

For 12-14 cells you also could take a lehner XL2800, though this is a bit above your budget (the 9L has got more torque bytheway.)

Considered your budget, and amount of cells you want to use, i would personally take the 9L 9920 over the hvmaxx without a doubt.

You might start giving your finger some lessons in being carefull onthe throttle, because the 9L is able to ruin stock diffs and get your driveshafts twisted. if you want a setup that is milder on your drivetrain, get the hvmaxx, it will result in a less powerfull truck however.