I had the full Campy Chorus 11 component group installed on my Litespeed Tuscany frame in mid-June 2009. It did not work properly from the very first shift. Specifically: when I attempt to shift from the 18 cog to the 19, it just sits in the 18 and clatters. My bike shop called Campy and they sent them a replacement part they called an "indexing plate". It took 6 weeks to get that part. After it was installed, the problem was still there. In frustration, I finally called Campy myself and they told me there's a problem with a spacer in the 12-25 cassette (which is the one I have). They're sending the new spacer to my LBS, and they're going to send it to me to put on (I live over an hour away from the shop). My LBS called Campy, too, and they told them that there's no problem with the 12-25 cassette, it's the 11-23 that has the problem. Bottom line: I put a lot of money into a component group that doesn't shift properly, and I'm getting mixed messages about why. It's been over 2 months now, and I'm an unhappy camper.