Have never flown Korean. Cathay and Singapore were business class and those were worlds better than Lufthansa or British Air or Air France (forget about Continental) — most of my US flights have been coach.
I remember having to fly once from Madrid to Munich on Lufthansa and a german colleague told me how lucky I was because Lufthansa had just finished a multiyear project where they studied the problem of seating and had developed and installed brand new super comfortable ergonmic seats in all the flights. When I got on the plan, the seat was leather and hard as a rock, no give at all. It was like sitting on a flat wooden bench.
Last time I hear "this is the ideal in German comfort" and look forward to trying it.