The best teams in FIRST make it to Einstein. They don't have motorized carts.

It means you really don't need one. With the weight and size of a motorized cart, you can have a beefed up normal cart. I've seen carts carry tons of batteries, a toolbox, a screen with scouting data on it, and even one that weighs so little it's like pushing a 150 pound box with a tap of the foot.