Well, if its any comfort (and I'm all about comfort), after my trip discussed in this thread:
http://www.flyertalk.com/forum/delta...flat-beds.html
I can say I am now officially changing my vote to the A333 as the most uncomfortable J seat (overtaking the KLM 777 seat discussed in the thread above - some of the coping strategies mentioned there worked on the 777 - not on the A333).
And yes, I DID take a 767ER on the last segment and would rate it significantly higher than the A333. Faintest of praise, but still...