Vertical ST is probably the best choice if you are determined to go for it - lighter, less useless plastic, 26mm adjustment range at the heel and fairly functional brakes in fairly wide sizes.
If you habitually ski with a DIN of 10 or higher (actually, say 9 or higher) on alpine bindings you might want to consider the FT12 (probably should get the power plates as well) or the Plum Guide. Keep in mind that Dynafit will offer a re-designed new lineup next year that will incorporate several interesting design changes, but no one seems to have any idea of how well they will work (or if they do they aren't talking on the normal Dynafit-centric channels).
Because of the relative lack of elasticity, Dynafit DIN numbers (or RV numbers) are not comparable to alpine bindings' numbers, you will probably need to go a little higher to get the same retention, especially on vertical (upward) release.
You would do well to go to Lou Dawson's site,
www.wildsnow.com
, and read all you can on the quirks associated with Dynafit use - there are quite a few that are essential to successfully using the binding. If you have friends who are already experienced Dynafit users, it helps to go out a time or two with them when you first start using them.
