That totally is dependent on several factors, are you going to race only, race mostly, bash mostly, bash only. Do you want a heavier truck with a big block, or a lighter truck with a small block. Heavy Bashing, moderate bashing, how much you want to spend, ease of repair and rebuild. what does your LHS stock parts for and what do all teh otehr kids play with.
Race only, Revo is ultra race ready out of the box, and pretty good for bashing. Moderate/easy for rebuild and repairs. Middle price range of group. Savage takes a beating and keeps on ticking, ok for racing. Difficult/moderate repairs, but lack of repairs and least expensive of group.
LST, many arm issues. LST 2, pretty good racer, pretty good basher, no idea on ease of repair, but most expensive of group. MGT, not sure on this, heard it is a decent racer, decent basher. all you others feel free to expand upon or detract from what I said.
HTH
Rod