y not my year?!?

Ive been looking for a great performance exhaust that isn't a tin can for quite soom time now.. but when i find a exhaust that could be the one the year all ways stops at 99! what is the differance between my 2000 and a 99 to where it cannot fit the same exhaust... also do you guys know of a great performing exhaust that isn't a trash can? i was looking into the rs*r but i want the best for my buck! thanks

I think it may have something to do with the header/cat length. All the big names are good, but yea, they're expensive. The GReddy EVO is nice.