^ between brands? The main issue is filtration - if it lets in particles that the stock filter wouldn't then there's a problem. From the Auto Salon test, for filtration it's better than all except the K&N (wouldn't use anyway because it's oiled)

In terms filter life and maintenance, who cares - for $30 it may as well be a disposable filter. As long as it lasts the service interval it's all good.

But then again $30 repco/supercheap brand filter just doesn't sound right for a WRX does it... the guys on the skyline forum love em though haha