I will install a deore XT hydraylic disc front (currently i have a mechanical disc) and also have tektro v-brakes on the rear wheel. They are ok, but on a bit of mud they squeal and don;t brake well then. I am thinking about buying a deore XT rear v-brake, Should I? I mean, is there a noticeable difference in braking? (are the XT's much better)? I have ZAC-19 rims and Rithey Z-max tires.