Both the dark impact and the rising storm are 4WD but the dark impact is a much better buggy. It can be raced at the club level and it's pretty durable as well. the drivetrain will take anything you wanna put in it from a mild brushed motor to brushless on 3S lipos with very little problem. The rising storm is a very good car too but it lacks some of the better parts found on the DI. While you're looking the Tamiya avante MK2 and the keen hawk are all the same as the DI. The only difference is the body and wheels. If you're not in a big hurry and can spend a couple more dollars tamiya is getting ready to release the Durga. Everyones saying it's the next true racer from Tamiya but no one knows how well it'll hold up to abuse.
http://www.tamiyausa.com/product/ite...oduct-id=58395