I have a medium to narrow foot and they fit just right. If you wear a 10-10.5 then they might be a bit tight on you if you wear a typical thick mountaineering sock with them. The boot is so warm that you can get away with wearing a medium weight sock and have them fit just fine.
The liners are made to be thermo molded. Local ski or climbing shop can fine tune the fit.
I'm in Bellevue, WA.