I guess I'm still kind of frugal, even if I'd be using miles rather than cash for a premium cabin. For a domestic (USA) flight, or any flight under 10 hours, coach is fine and the "you're getting there at the same time as the premium cabins" applies. Even if it's overnight, I'll usually sleep enough, especially in a window seat.

For a flight of more than 10 hours or if it's a flight with a lot of segments, I'll try to find a saver award ticket in a premium cabin, but I won't be heartbroken if I can't.

When I do a big solo international trip, I actually like to start the trip in coach -- it gets me "in the mood" and it eases me into the feel of my destination, since I'm near a bunch of other people from, or speaking the language of, the place I'm headed to. Then if the trip back is long enough, I might spring for the premium award, which kind of mitigates the sorrow of the trip ending.

When I flew to Madagascar via three overnights (JFK-LHR, LHR-DXB, DXB-NBO), it was definitely worth the miles to go in business, so I could sleep better, use the lounge showers, and be better-rested for my days in each place on the way.

And when I took my girlfriend to Asia, business class was worth it (especially on the old 90K US Airways award) because she doesn't sleep well on planes and we went overnight to ADD and then overnight to BKK and on to NRT.

I'd like to try a super-premium first class (like on Etihad or Emirates or Singapore Suites) just for the experience (as I recently did to try the KE Kosmo 2.0 suite), but I wouldn't say I have to have it every time.

I don't think I'd justify paying cash for a premium cabin, though. A couple thousand dollars, or even a $500 upgrade, is a lot more than I'd pay for the equivalent hours in a nice hotel room.

Seth