Yeah defiantly get the STH 12. Make sure its not the STH 12 OS though, thats the z toe version of the. The standard STH 12 is the one with the driver toe.
The reason to go for the STH or z is both for the driver toe, which is one of the best toe pieces on the market, and you also get a much stronger more durable heel compared to the z.
Dont get an STH 10 though, that is a z binding in disguise.