Diacompe used to make some really beautiful Gran Compe centerpulls. They had ball bearing pivots. They were used new on Univega touring bike in the early eighties. Rivendell sold them a few years ago, but I think they're gone now. Weinmanns and ordinary Diacompes work well and look boring. Mafacs are hard to set up well. I had Mafac 2000's on my Gazelle touring bike and didn't like them: coudn't stop with a full load. Then I replaced them with Univeral 51 sidepulls, and that was a great improvement. Fifteen years later, my hands are too weak for the Universals, and I stop by crashing into poles. I'm contemplating a return to centerpulls. In retrospect, the problem with the 2000's was probably the fault of stretchy cables and a wimpy cable hanger on the headset.
Leonard Bulger
Ann Arbor, MI