As someone who will be in the 80+ category in less than three years, I think an important question hasn't been answered yet: what class? I can see wanting to get out of the plane every so often if I'm stuck in the small seats, but in F or J, time in the air isn't nearly as much of an issue, and I've done a few US West Coast - Oz trips in Virgin Australia PE recently without pain. (My wife, who is also 70+ though not as much + as I am, and I flew LAX-MEL and SYD-SFO a few months ago in J. The thought of making a long trip even longer by stopping off here and there, unless it's the only way to get out of a tiny seat for longer than a trip to the lav and back, is not attractive.)