I get a kick out of all there efforts to increase stopping power. Three of my bikes have more stopping power available than I find good or beneficial for good control, especially when I need to slow down a lot. (Two Shimano dual pivots, not new and Shimano old-school cantilever.) I de-power those brakes with V-brake levers and find I can stop much faster safely and without surprises. (Most of my brakes have various Kool Stop pads of normal road lengths.)
I have found however that some calipers are poor. With levers that work well on other brakes and my hands, I find the old Campy NR brakes poor in the dry, scary bad in the wet. I won't run Weinmann centerpulls or their copies in front, especially on a bike that will see rain. (I put them in back and use Mafac Racers in front.)
The funny one is that the $10 unmatched used (and partially trashed) sidepull calipers I put on my ultra cheap fix gear had, with ordinary Tektro levers, great dry road stopping power!
Ben