[slimthelineman]

Based on batteries the 5200 should run longer. Amp hours are amp hours no matter what I think the main difference is the motors and tall gearing. I would think the 1518 would draw a fair amount more than the 1515 especialy with tall gearing. Like stated above as well driving style is everything. I tried this one time at the track by timing my practice run to lvc and then handing it over to a fellow racer and doing the same. He's an ex nitro guy and his "on-off" driving style knocked almost two minutes off run time.