Like everyone is saying, if your daily driving your vehicle then you might be able to get away with traditional parts shop blanks. That being said, there is a reason why engineers have specified the rotors/compounds used for they brakes on your car.
Jory(LilDrunkenSmurf), i would stay away from that idea, in a simple caliper system i would shrug and say ok but your running brembo 4-pot brake calipers which generates stopping force much greater than a normal smaller caliper which if you use a poorer quality rotor you will end up warping/glazing the material quicker and find your braking efficiecy just wont be right. You have an STi now, not a civic ; )
For the OPP (RSX Driver), if your traditionally driving around the city without heavy braking and install the rotors correctly with proper break in, then you should be able to avoid most warpage/glazing etc. Just be careful if you try and slow down from 190- 90 in a moments time, it may be the last time those rotors will work properly (assuming your on a track..........)
1994 EG6 -1998 DC2 - 1993 S13 - 1993 S13 -1994 S14 - 2001 BMW E46 - 2006 BMW E90