RE: What's the best Brushless motor for Off-road?
I think Novak is pretty much still on top for their large selection of tuning rotors, 'L' series motors (as needed), and their easily torn down 'ballistic' motors. Though if you are doing stock racing Hacker E40's provide ~20% more torque than an equivelent-turn Novak (pre-ballistic) at equivelent RPM in dyno tests, at the cost of efficiency (look at the dyno tests they did on rctech). Do not that if your track follows the official ROAR rules, the use of tuning rotors is now illegal for the most part (see the ROAR racing site for exact details).
If Castle would take what they learned in making the Neu-Castle motor and put that knowledge into making a good 1/10th scale motor, sensored, that would be the king of them all, but they are yet to do that. Not much has changed in a year really, though the mamba max pro ESC could change stock racing if it lives up to what castle says about a hybrid sensored/sensorless mode.