Replying to Is there much difference between models of Full Tilts?

Is there that much difference between difference Full Tilt models? A quick review of the Full Tilt website reveals that they all have a last of 99mm, except for the Booter (102mm), and the flex - which can be completely changed for any of the boots anyway. Is there any other real differences, in terms of shell and liner, between the different models? Or is it just different aesthetic designs with different boots?