The Yamaha student model bass is nice(r) than most others. The metal keys are a bit more rigid than the Selmer USA, which means fewer trips to the repair shop. The Yamaha also has more adjustment screws.

PSA: If you're going to march bass clarinets, ya gotta know how to repair them. They'll bend and break at random times all season. The Yamaha's adjustment screws make these repairs a bit easier on the hands.