it was not just Sheldon that hated them Tom Cuthbertson of Anybody's Bike Book Fame (my bible in high school where the nearest bike shop was 140 miles away...same distance as the nearest Starbucks is to my home town today) had no use for them (or simplex plastic derailers). My experience was they did not stop as well as the regular brakes.
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Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or for Raleigh International frame fork 58cm)