How about a Subaru Legacy GT? You get the turbo and AWD of the WRX, but it looks a lot more grown up. With a simple stage I flash you can hit around 300hp.
Mine's been a rock and is pretty fun. Engine/transmission have been around forever and are solid. The overall build quality of the interior/etc are just so-so though.
When I bought mine, it was 2.5 years old / 30k miles and I paid $15.5k for it with the premium trim ( turbo, leather, moonroof, premium sound, etc )