From a super-narrow footed skier, just for general future reference for the narrow-heeled Divas out there:
I measure 27.5 on the brannock measuring thingy.
I had a bootfitter (in Allentown, PA) refuse to bring me a 26.5. I actually had to argue with him and he finally brought me a 26.5 but grumbled about it the whole time and then fell off his stool, and I'm not a mean person but I wasn't sorry.
27.5 was always sloppy-fitting to me, no matter the brand or volume designation.
To get a sense of boot fit without numbers attached, take the liner out of the boot and put your foot in the shell with your toes just touching the front. If you can fit two fingers between your heel and the back of the boot, it's roughly recreational fit. One finger= roughly performance fit. That at least gives you an objective idea of what you will and won't be able to get away with as far as liner pack-out and volume.
I always ended up in Lange LVs because they are the lowest low-volume boots that aren't race boots. The best-fitting boots I ever had, though, were junior race boots. 92 last width. (Thank you to Start Haus in Truckee for the fit and recommendation). But then I gained weight and those boots didn't quite work anymore along with a lot of my clothes :-(
Now I'm in Lange LV AT boots and they are great; they fit fine; the only thing I'd do differently is get a stiffer flex because I guess AT boots are less stiff in general (not my wheelhouse, that's just my understanding).
But to make the saga more epic, I switched to snowboarding, and it's REALLY hard to find narrow boarding boots!!! Argh! I'm in Rome Bodegas, though, and they are good.
Anyway, cheers to good heel-hold and pain-free skiing!