Originally Posted by canuckbiker
If you want the best performance, yes. Or you can use a Jtek Shiftmate that will allow you to use a Shimano derailleur.
Actually, I think he can use a Shimano der without much problem (much). However, he needs the Campy cassette. If he goes with a Shimano cassette, then he will require a shiftmate to account for the differance in spacing.