I am looking to upgrade my setup. I currentle run some Rolf Dolomite wheels with Avid SD 2.0 brakes and XT intigrated Shifter/Levers. I have never had Disc brakes but purchased a set of XT/Mavic XC717 with XT centerlock rotors. I am looking to get some Avid BB7 calipers. But I am riding a light weight bike @24lb on a large frame. How much weight would I be saving by getting a new set of shifters and some light weight Hydros I am saving some weight running the intigrated shifters/levers aint I. Should I just get the avid calipers or sell the shifters get new shifters and new Hydros or should I just sell the Rolf wheel set, sell the XT/Mavic XC717 sell the rotors and buy a real light weight set of rim brake wheels and avid SD Ti brakes. I never had any problems with my cheapo Avid 2.0 brakes which I can't say for Shimano XT V brakes.What to do.