I posted this on the "Ask the Boot Guys" forum, and didn't get any replies, so I figued I'd try over here....
I'm in the market for new boots, and had an interesting discussion with my bootfitter about the differences in geometry among the Head Raptor, Lange RS (=Rossi Hero) and Dalbello Scorpion. He pointed out that the Raptors have significant varus in the clog's heel -- about 3 degrees (if you look at the boot from the back, the middle seam running up the back of the heel tilts outward) (the boot board itself is level -- only the clog has the tilt; effectively it's like standing on a level surface and having your ankles slightly tilted out). We didn't have a Scorpion on hand, but he said it has a small amount of heel varus (maybe one degree). The RS/Hero have no varus.
In addition, the Scorpions displace the foot laterally (outward) by a few mm, the idea being to place the ball of the foot closer to the inside edge of the ski. Just based on leverage, this would seem to make it easier to tip the inside ski, and harder to tip the outside one. Neither the Head nor the RS/Hero do this.
In summary, the Rossi/Lange are neutral with respect to heel varus and midline displacement, the Heads have strong heel varus but neutral displacement, and the Dalbellos have moderate varus and some midline displacement.
Any comments on how these differences will affect skiing?
Interestingly, unlike cuff alignment and canting, a shop alignment can't tell you which of these geometries would work best for you -- they only clearly reveal themselves during skiing. So it would seem the only way to determine which is best for you would be to set up all the boots correctly (including temporary cants), and demo each of them while being videoed.