I LOVE the 80mm f/2, but damn this is a tricky and sometimes frustrating camera to use! It's got some of the weirdest field curvature i've ever seen, and the backs don't do to well to keep 120 flat.
It's an intriguing departure form the Mamiya 645AF, the Contax is better in some respects, the Mamiya in others. If this was still the 1990's and I was a professional, I'd use the Contax for weddings and outdoor portraiture that would be generally shot wide open, and use the Mamiya for everything else. The Mamiya 80mm f/2.8AF I believe is technically a better lens, but the Contax/Zeiss 80mm has some of the most interesting and unique rendering i've ever seen.
Has anyone else had similar experiences? Here are some recent scans of a mix between Ektar 100 and 400H off the Contax, enjoy!