Once you're moving there really isn't any difference if you have both systems set up correctly. The only real reason I will never use sensorless for off road racing is for mid-air corrections. If you watch any of the fast guys who drive aggressively, it is common to hit the brakes immediately after coming off a jump to bring the nose down, then punch it to get the nose back up just before landing. This allows you to land squarely on power. Fractions of a second mean the difference between a perfect landing and an epic wipe-out and the small inconsistency in the start time for sensorless doesn't make the cut.