Yo Rolland:
Roland makes three models of amps. I have one made for the Keyboard, I think it's the 500 model; sounds great and I do believe there are enough dials on it to make a git-fidle sound fine too. You can test one if you can get to a store that carries the Roland line. The biggest model is HEAVY; the other two in the line are lighter. But, the big model comes with clips for wheels and some dealers toss in the casters.
Check out the Roland Rolland.
Green Hornet