Mine is somewhat odd. My upper lip is very close to center, but I'm left of center with my lower lip. I try to play 50/50 top to bottom, but I slide to 1/3 top and 2/3 bottom when I start to get tired. My tone has improved well as I've only been playing again for close to 3 months. Stamina is getting better but still working on the range, though for now I can reach all the notes I need to.