HARD - My original Grasshopper.http://www.tamiyaclub.com/showroom_model.asp?cid=15138&sid=2193
The second Tamiya I ever owned and still going strong. Ok, so it has more hot-melt than plastic, but you can kill it and in ten minutes it can be re-born! It used to do battle with my mates Pajero, but now it gets stomped by my "King Black-head" http://www.tamiyaclub.com/showroom_model.a...=18252&sid=2193 . This gets driven by my 6-year old who loves to drive it over the top of Dads Hopper! When he's not chasing mine he uses it for shifting small objects from one side of the road to the other.
Also HARD: Blackfoot/Monster Beetle with a lexan body - not in my showroom. Still my favourite truck to drive.
MEDIUM: M-chassis cars. Great for going fast but I'm not into trashing a body that I have spent ages painting and decalling.
SOFT: Any new runner I get. Gotta try them out - preferably without breaking anything. Unfortunately I often do this in my factory and there are lots of objects to bang into. Can get some good drifts on the slippery floor though.