I've got a slash... they are a fantastic budget basher. Change out the wheels for something with a little grip though as the stock just suck for anything on the track. If you are racing in spec class with the truck then you might be stuck.
Couple things I did to improve the roll travel:
Lower the server by mounting it below the deck. Change out the shocks for some B44 shocks running green back, silver front. I run 20wt oil in the back and 45wt oil in the front. That gives it just enough sloppy grip on loose dirt tracks. If you can change out the tires, that will be the biggest improvement you could ever do. Even if you change them out for two 1:8 scale buggy fronts... anything on the wheels helps.
The problem with the tires is they use an extremely large sidewall with little ground patch. I thought one way to counter the wall would be something like a two layer foam, soft out/hard in for low speed grip to high roll. It's just the tire.
The slash makes a fantastic 8th scale buggy though... check out the Project \Backslash
http://www.ultimatetraxxas.com/projects/backslash/