Mesa,
I built some 1/8 off road buggy cars for a friend (Thunder Tiger brand). I never owned the 1/8 scale variety, but had lots of fun with the 1/10 road cars, DTM racers, and buggies. The buggy cars were the most reliable, but the DTM had a 2 speed trans, dual disc brakes, full suspension, and a slightly oversized motor. That thing hauled. But the boats were by far the most fun, with run time / maintenance at least 4:1.
I almost always used Thunder Tiger engines,and they were superior in my experience.
Now moved on to bigger toys, starting with the Ferrari, then adding the Ginetta, and now an RCR Superlite Roadster. I think that should be plenty for me.
BT