Oh, they give a great show! Don't hesitate to use them. We did it 2 years ago and as I understand there were ticket issues but that was because someone dropped the ball. Asking them to temper the music they play would work fine but truthfully, I don't remember it being all that bad.
Try to plan it for a dull time of year, not in spring or fall as it competes with kids sports.
We are thinking of trying the Harlem Wizards as a fundraiser in the spring. Does anyone have experiance with them? It seems like a lot of work and I don't know if is worth it or not. I heard the music they play is not "kid friendly".