well it all depends on the setup of the brake to be honest mate maggie's are probably more popular than discs on the rear, i ride a 221 ti 07 dual disc and the rear brake is very good but it depends on what you prefer, if you had e.g a maggie on a smooth rim with green cnc cousts or rock pads that would probably be just as good. it all depends on the setup of the brake hope i've helped mate