kind of depends on the track layout. If it's super smooth, and down-siding jumps is key...then i prefer very little to no rebound. If the track is littered with bumps, rutts, tiny landmines...rebound is good to keep the car responsive, and charge through those bumps.
You typically want faster rebound up front and slower in the rear. Fast rebound in the rear will cause the car to "buck" aka pogo stick effect. I come from a DH mountain racing and its a shame theres very little dampening tuning on RC shocks
