I think 2000 and newer are all the same, so you should be fine. You can compare them and tell by looking to see if the bolts holding the rotor are recessed or not.
+1. I believe this is correct. Seems hard to keep it straight, but I believe when the IS came out, in 99, they made the switch. The IS's were all the same, 99+. I am not so sure if the std. made the switch in 99, or if it was 00. But, if 2000 or newer, all should match up fine.
If you are switching between early and late models, then use the rotor that matches the wheel, and all will be fine.
MP