Never to run the car full throttle without loading even brushed or brushless motor, the RPM will get too high and will damage the motor either by too high temperature / breaking the motor "heart" due to gravity / high rpm.
In my opinion Novak's motor is the most durable one in the market now, I've got mine 4.5r over 100 packs of batteries and still rocket fast, while my LRP X11 only survive for like 20-25 packs and it's done already.