I completely agree about U2 - most of the remixes of their singles in the 90's (especially for that 1990-2000 compilation that came out in 2002 with Electrical Storm - the last music of theirs I ever gave a shit about).
A few Sympathys aren't too, too bad. I detest the 'I'm Free' remix. You Got Me Rocking is insanely awful - that is THE worst of all of them. There is, however, a remix of Harlem Shuffle - not the one on Rarities, but the one on the Flashpoint Collectables disc 2 (also part of a box set - which i didn't need to buy because I had the same bonus disc already).
THAT is the ONLY example of a remix which surpasses the original for me. I do like the longer Miss You from that better to, but that's not as much of a CHANGE as much as a different edit. The Harlem Shuffle I'm talking about... those breaks, key changes, and organ solo - it's WAY #$%&ing better than the version on Dirty Work. It sounds fantastic and actually made me like the song, whereas I thought it was a cheezy throwaway cover when it first came out with the silly cartoon video.