I use suicide levers on my touring bike. I don't think I would find staying in the saddle for 8h half as pleasant as I do now, if they weren't there.

Those are original Shimano Exage levers from the early 90s I own. They are made of steel, painted black with rubber, very similar to those pictures above. I use them with old Shimano Deore II cantilever brakes, Deore XT braking pads, aluminum Mavic rim. As said above, wheel have to be true and distance between rim and brake pad minimal.

I can't say much about those much older, all aluminum levers. What I feel tho is that riding this bike is much safer (and comfy) with those levers than it would be without them. They never work as sharp as aero levers, but they are enough even when I'm riding fully loaded.

Cheers!