Remember, everyone, that he plans on building the car for STF. Sure the SVT is great right out of the box, but once you start slapping coilovers, swaybars, etc. they basically become the same car chassis-wise. The SVT does have bigger brakes, but brakes are upgradable in STF as well. So if you're going to build the car to STF specs, get the car that has the best powertrain. The SVT has really good pull between 4500-7000 RPM, but it's only a 2.0 liter with unusually tall first and second gear, which making any low-end grunt basically non-existent. Getting a 2.3 liter ZX3 might actually be the way to go. It would be better on slower, tighter courses for sure, with the SVT having the advantage on the more long legged courses.
Try to get one that's good for an autocross car. And by good, I mean without a sunroof and winter package (w/ traction control). Though the traction control can be tuned out (kinda) in STF, if you want it being in BC and all.