I use ultimate pads and they build up after awhile. About twice a year I take off the rotors and scrub them with break cleaner and steel wool to remove the buildup. This is a quick and easy thing to do that cost nothing. If you still have the warping feel true up the rotors (about $10 each). You don’t need new rotors until your old ones are too thin to true anymore or crack. I have done it up to three times on stock rotors. People have become so use to just getting new rotors cuz almost every mechanic will put new ones on rather than true them cuz they make more money then.

You can try a pad switch, you didn’t say what ones you are running now but most performance pads build up compound on the rotor. You can switch to a less perfomance pad more OEM like.

 

A basic truing of the rotors at the local auto parts store, fluid change and pad replacement will do wonders. I recommend the Valvoline Sypower brake fluid it’s cheap and great. The pads you will have to research to find what fits you.

 

If you want to take a good interim step, try the Stoptech Stage 2. I just got it and I think it's a great compromise between stock and a big brake upgrade. In fact, the whole deal (including 4 new slotted rotors, Axxis brake pads, new brake fluid and SS lines) cost me less than the local mechanic and Subie dealer said it would cost to replace with stock rotors & pads.

Also gets you prepared for the world of quick/jerky stops.