I tried Dd with on a load of different Frames, Brakes and rotor sizes, None if which i got on with. I tried BB7's (New and older styler, 160, 185 and 205mm rotors) BB5's with dual 185s and then with a rear 203, Mono trials with a Rear 205 and a front 185, Hope C2's/Avid Juicies/ Various Hayes breaks. None of them gave me what i'd class as a great brake, The Mono trials were ok but didnt bite too well, BB7's were the opposite, shit loads of bite but no hold No Rear disc i've had ever compared to my Magura (Standard eisbar magura, Braided crossover, 74 Kingz tpa wheel With CNC Echo pads/Heatsink reds) Although i've never tried front and rear maguras so can't comment on what thats like, i think a front disc, rear magura is the best combo although if i had to choose between souble disc, and double magura I'd Pick Double maggie.