The vetting system will have to be tailored very strict to insure they have the right personality and drive to survive such a mission. I could swear I have read of such testing to have taken place already to get some benchmarks to apply to actual travelers.
I'd say creative doesn't hurt: honestly, I know quite a few folks who would kill to run a D&D campaign or the like uninterrupted for months on end. And your players won't have other obligations to catch them off guard :)