I'm 6ft and the 737 was pure torture... one step removed from water boarding! After 1 year on it, I was seriously considering back surgery. Moved to 7er and after 1 month, all my back problems were gone.

From js'ing on the 320, it appears to be the same size cockpit as the 757. So the clear winner, based on the amount of time one spends in "the office".

P.s., A second js in the 73 torture chamber cockpit for 5+hr legs... um, no thanks... wouldn't do that to my worst enemy... well, maybe my worst enemy!