The 5 speed is not a problem honestly on anything past 03. They made the gears larger. They can hold well to stage2+ power.
It's a good car they have a slightly softer ride then a WRX. The I know they make similar dyno numbers. Its a subaru really when it comes down to it but you get way nicer interior.
Then again my wifes outback is nicer inside then my car.
they did have a ton of warranty issues. The saab guys were clueless and they would not send them to subie techs,.