Being strapped in and immobile for hours is worse than a 4 hour OOD/JOOD stint, from the back/arse pain aspect.
Other than that, if I am up at 0230 I better be drunk, or flying...
Whatever the 0200-0600 watch is nicknamed, it SUCKED.
We had no helo the last 3 weeks of my last cruise, so the Captain made the JO pilots stand watches to give the shoes some rest. Bad for us, but he was trying to get a "crew rest" and "crew day" thing rolling for the JO SWO's.
Some of the pilots had been talking to the SWO DHs (all LTs), and we guessed that the SWOlings would get more quality work done, if they had a SCHEDULED 4 hour "no interrupt short of GQ" sleep period, and another 4 hours dispersed as able (tried to get 8-straight, but with quarters, watches and OPS/INTEL, it was not always possible).
From what I saw, the DH's were impressed with less errors, better work, and far better morale. Not to mention, less tired people on watch was better for avioding near misses.