Cars:

It's been almost five years since I've had anything to do with piston engined rc cars, but at that time the Dynamite line was inexpensive, intended mainly for beginners. And being cheap they didn't lose a lot when they destroyed their first engine. Some people bought a Dynamite engine for replacement, but most bought higher quality. Their engines could well be much better now.

The Megatech airplane engines seem to be good, powerful, and long lived. If their car engines are the same I wouldn't be concerned about buying one.

But do remember I have no hands on experience with the current engines.

Bill.