After playing with my Hayes discs for a couple weeks i've come to realize something. The 1st guy who develops and markets an adjustable caliper mount will become a millionaire !
Seroiusly, i cannot understand why they don't make these. A mount which would have screwdriver accessable adjustment to line up the caliper with the disc. It would be adjustable for both slant (for lack of a better term) and distance towards and away from the wheel. On both my front and rear the discs and calipers are not lined up straight. On the rear i had to grind some metal off the caliper mounting area on just one side of the area that seats against the adapter. Otherwise the disc goes thru the caliper at a slanted angle that makes it impossible to accuratly adjust it and expect it to stay right w/o rubbing for more than a ride or 2. Not that i can't deal with it, but this would make it far easier to get the calipers adjusted correctly on the disc and would eliminate the learning curve for those new to discs completely. Absolutely perfect adjustment of the caliper would be possible.