Hmmm, this would be a pretty interesting superpower, although I'm sure the potential injuries from doing this wrong might be a touch more severe than broken bones! Definitely, it would be a great thing to find out what other potential universes exist and how things have played out there...
I would have to point out that sliding between universes, especially if the fundamental constants of the universe were not secure could lead to you sliding into one of the many "dead" universes where the laws of physics (well, actually the constants that govern the settings on the forces) might even preclude atoms from forming... that could be a big downside!