I think if you are open to either platform it all comes down to what you plan on doing with the car. Power/Handling so on and so forth. How you want it to soun (if that matters to you) and how its gonna look.

Personally I choose an STI because I've always wanted one. I got an 05 because its the stronger of the two peanut eye's.

As much as I like the way a modded Evo looks, how some of them can sound, and the power they are capable of, I'd never drive one because of the majorial (yes i made that up) demographic that owns them and what they (the car) says to me everytime I see one.