Interesting. I have the same setup (Contax + P30+) and have both of these lenses. I planned on keeping them both, but the overlap in focal length has made me consider selling one of them. Both are manual focus lenses, but you get focus confirmation with either one. The upside of the Hassy 110FE is that it's F2 versus the 120mm Makro at f4. The benefit of the Contax is that you don't have to stop-down, i.e., I can shoot with the Contax at f8 and still be able to easily manually focus because the lens stays open til exposure. Just thinking out loud here, but if I were to only keep one, it would probably be the Hassy.
What was your reasoning in deciding to sell the Contax instead of the Hassy?
I finally was able to by the beloved hasselblad 110 F2 FE this week for my Contax 645/P30 setup. I must say it hasn't came off since. Anyways the moral of the story is I need to sale the incredible and hard to find Contax 645 120 macro lens that I just was able to buy. I bought it from the original owner who swears that he never used it, and I believe him by its condition. It comes with the lens hood and clear contax filter that has been on it since day one. I know I'll regret it and want it later on, but for now its on the block. You guys know what these go for so send me an offer..........