Just got a '75 peugeot mixte (fairly low-end mix of components I think) with Mafac "Racer" centerpulls. Oh man, what a revelation! You can fit them with long canti-lever pads, and they have some stopping power. They are way better than even the 105 sidepulls on my mid-80's Trek, which I always thought were pretty good. And anything less than 105 sidepulls, like old Dia-compe, are junk and should be disgarded, imho. I even removed some weak mid-80s Campi Gran Sport sidepulls from my Italian bike.