To be honest, if you're looking for a "street beast" you're probably not gonna find it in an import. I know I'm gonna get flamed for this, but it's much easier to make a beast out of a V8 than a 4. Yes, you can make any car really fast, but the question is, how much work do you have do do to it? In one of the latest car and drivers, they had a face off with a bunch of high level import tuners. I forgot which one one, but a bone stock corvette beat all the highly modified imports in every event. Not that I'm saying get a corvette, but it's an example of how nice torque is.
A fun one would be a classic muscle car. You can do just about anything you want to them, if you find the right one it's relatively inexpensive, and they're really easy to work on (plenty of room in the engine bay on most of them).