Brother had a Saab 9-3 when they still looked like Saabs. The only time I went in it we drove about 200 miles without stopping and all I can remember is how comfortable the seat was.
Personally, the comfiest seats I've ever had were Ford Escort S2 RS Turbo Recaros, non leather. With the thigh supports out no seat has come close on long journeys.
got a new van, but the saab seats in the trafic were so good I did it again. just need to weld up a frame to fit the 60 part of the 60/40 rear seats out the saab to the passenger side, but its uncanny how nicely they fit.