I have an 04 Evo, and I test drove the WRX, STi, and the Evo before I made my final decision... I felt that the build quality was higher on the Evo versus the Scoobs... For instance, when you shut the doors on the Subarus, it is really tinny, and not positive feeling, but on the Evo it feels like you're working a cadillac door... Huge difference in feel. The STi is faster out of the box, and the six speed is cool, but a couple hundred dollars spent on the Evo will lay the samckdown on the STi, and you'll have a nicer quality car to boot.
Mike