Verified answer

Research these forums for advice on intakes. There may be instructions on how to make your own for less. As a WRX owner, I didn't waste my money on an intake. I removed the intake silencer in the front fender and added a Perrin panel filter for less money and similar performance gain.

Your car can benefit from an intake but not a whole lot. And it has to be an RS specific unit. Even year specific since they keep changing between MAF and MAP st ups so make sure it's for your year 2.5RS. As far as brand, AEM, Injen, any major brand will be good. It's just a tube with a filter on the end. Just don't buy a no name Ebay one because it has to be the right diameter pipe with bungs for sensors in the correct place and the no name ones may not do the research and just make whatever looks right.

The difference:

Spend 200$ on intake: Get 1 horsepower.

Spend 10$ on intake : Get .9 horsepower.

Seriously. There's no point in spending money on name brand intakes. At best, over your powerband, they give you the same gain as anything else. And sometimes, you lose power.

Don't bother with them.

the intake is different for turbo and non turbo.