They don't have long battery life either. The only reason it's worth getting one of these at WDW is because the swaps are free for a fully charged one.Three freaking dollars‽‽‽ Seems to defeat the whole dang point of these things.
Either way, you can buy a portable charger on Amazon with much longer battery life for less money than these cost in-park and not have to ever worry about getting to the point of a low charge. The battery on others is made for long days unlike FuelRod, where it seems they are made for the purpose of these vending machines existing.