Having had the XM3 and now the XM5 for a few months now, the difference in size of the upper headband doesn't make any difference to comfort. I have a rather large head (62cm circumference) and it's super comfortable. I hope this helps you in your choice.

Hi,

With the WH-1000XM5 you can enjoy all-day comfort thanks to the silent design.
These lightweight headphones have a beautiful "soft fit leather" finish. The material fits close to the head, exerts little pressure and blocks out ambient noise. The WH-1000XM5 are comfortable to wear thanks to their low-noise design with stepless slider, seamless swivel and hanger.
You can find more information on our support page.

Sony Europe