In prep for the Bixler Cup, which is more about endurance than speed (but still speed, a little), I did some testing on a smaller battery that conforms to the power limitations (15kWh max, I think). My math showed that I would have the best endurance on a 2S 2000mAh, and still have enough thrust to fly. The question is though, how much slower will I be? TEST IT!
Without knowing what the Pace Plane is (they haven't announced it for FFWest, as of this post), I can't know if I'm really too slow to stay in the race. I guess we'll just have to wait and see!