We've just got to hope there aren't any major catastrophes involving life early on. Personal space travel could easily go the way of Concorde and commercial supersonic travel if companies like SpaceX and Virgin Galactic don't get it spot on first time.
(Moment's pause to remember and respect the Challenger and Columbia Astronauts, and the Russian Cosmonauts who also gave their life.)
As I think about it though, I think of the few brave people I know who would be willing to take a one-way trip to Mars, as long as they were starting a colony.
