[mechanicalbrain]

i did a sumo bot that ran on servos. keep in mind if the servos aren't quite up to the job you can get more power from the motors by giving them more juice than their rated for. note that this is actually safe as long as your careful. you can run a servo on up to 12 volts but the motor will get warm pretty fast and i would not recommend running them more than 4-6 min on a high voltage (and yes this will lower the milege of your motors but the speed and power increase is worth it).