I think for off road cars 4wd shold be better, cause 2wd is harder to controll in sand.. If you really have a heart to play monster trucks, buy a truck that is better like e-maxx, even it maybe a bit expensive, but the thing you get is in very good quality, so buy a truck with famous brands is better like Traxxas and HPI.. personaly I would choose Traxxas cause it is cheaper than HPI and their quality is also very good!!