Depends on your driving position too. I have a buddy that is shorter than me but drives like he's half way in the back seat. You can see his head from the rear door window lol
I'm 5'10 myself and i find the room in the back plentiful. Its much bigger than my E90 was.
Current - 2013 N55 535xi Msport SAT
Retired - 2009 N54 335i Msport 6MT
Retired - 2000 M52TU 323i ASA Supercharged 5MT
More photos of my car here