I love them both, but prefer the leopard. They are much easier to hold and seem to like it more. In my experience, the crested are more jumpy.
I've seen cresteds go both ways with regard to that - my brother has one that's basically a bump on a log. Mine is a bit more, um, "active" than that when being handled, but even so, she's by no means difficult, handling-wise.
Mountain bikes are for slow people, and reptiles are far better pets than cats & dogs!