One thing to keep in mind is the classes that are available for each vehicle type.
Assuming you run stock mostly or are looking for that speed initially, I am not sure 4wd even offers that or 19T at alot of the tracks, and when newbies combine with mod power, breakage on most vehicles becomes a reality. Who knows, maybe one day the class will be able to support at least a limited motor level like say 19 turn.
If 2wd buggy is supported, you may fine it more rewarding. There is just something about buggies how nimble they are and more challenging to drive.