When you get down to it, it's a feel thing and while there are differences, they don't really amount to a major difference that would compel you to pick one over the other. The big one is the jump skill but quite frankly I like them all for different reasons. Ignore people who tell you x class is no good for y activity. In short, write the three classes on scraps of paper, put them in a hat, draw one randomly and play it.