If we take a V30 Celestion as a familiar comparison, what I hear from the Fanes is a substantially thicker midrange/lower midrange that responds extremely well to gain, with a little more compression and less fizz. Thicker also than the Celestion Cream or Black Shadow 90 they make for Mesa.
Obviously there are differences model to model, and Fane makes several, but as with any speaker brand, there are family resemblances between models.
I like the character of the Fanes. I just haven't had any come in my cabs and I'm past the point of doing the necessary to install a set.
Edit: I think a set would sound great to replace the V30s in my closed back deep PRS cab, and would compliment the HXDA nicely. The V30s accentuate the top end a little more than I'd like.