If John Glenn could do a Shuttle flight at 77, I suspect you're overstating the difficulties here. People voluntarily subject themselves to 3+ Gs and 360 degrees pitch/roll at amusement parks daily, with fairly minimal levels of physical fitness being required.
You know John Glenn's name precisely because he is exceptional. I would certainly choose the discomfort of a 2-minute roller coaster over the discomfort of a 2-hour commercial flight, but... a man who set milestones in American spaceflight and was trained by NASA for a shuttle mission is hardly the baseline.
If the full 30 minute flight is like a roller coaster, I would be green by the time we got there and probably have a full puke bag. But I'd still prefer that to a 12 hr long haul flight in coach.
