There are a few types of "showstopper" breaks that can happen on a tour. Based on the reports and reputation of the Rohloff, I think that's one of the less likely failures. Doesn't mean it couldn't happen. But I think I'd be comfortable playing the odds on that. As it stands now, with my Alfine, I have 2 wheels, so I guess if I had a hub failure, I could have my spare shipped out. But really, in my years of riding hub gears, there was only one failure that I couldn't have limped along on, when my freewheel mechanism broke, and no power was being transferred to the hub. I've seen something similar happen with a gear cluster, so I guess that's not unique to hub gears, either. But even with a complete hub failure, there's always the possibility of converting to another drivetrain.