-
I ran one of these for London commuting back in the mists of time. The roller wears smooth and eventually fails to grip the tyre tread reliably, especially in the wet. It's also heavy. Hub dynamo is the way to go. Koolstop Salmons do improve the braking performance of Mafacs, but from a very low base. You are a brave man to ride them on long Audaxes! Modern deep-drop calipers are much more effective.
HarmanMogul-
I ride on disc equipped bikes, modern v-brakes and deep-drop calipers but I find these Mafac to brake strongly... If you have machined rims. The thing is: people often associate poor rim adherence and heat dissipation with the brake itself. It does brake pretty well with salmon pads. Not to mention that I'll of course swap the brake housing for something stiff and good quality cable. They are a PITA to set up correctly though, like many cantilevers, and are prone to brake sounds.
AlfredIV
Thanks ! Really helpful, I will buy these.
About your question @alialias, here is a pic. The bottom bracket dynamo works really well (powerful enough to handle a B&M IQ:XS 70 lux and a B&M tailight with plenty of parking light). You can even activate it by pushing the lever with your feet while riding slowly.
I do need to change to a hub dyno mainly because I hate noise, especially during audaxes or brevets. There is nothing more annoying to me than riding in a beautiful place with a bzzzzzzzzrrzzzzzrrr sound all night long. Secondly, as @mdcc_tester wisely wrote it, because it is under the fender and crankset, even with mudflap it is very maintenance dependent and not too reliable for long distances as I plan to do with this "randonneuse légère". And last but not least, by wheelbuilding I would be able to use modern day alloy rims with a machined braking surface. Much likely to brake as strong as Mafac Racers and Koolstop salmon pads allows me to!