I currently have Shimano 105 9 speed shifters on my 2006 LeMond. I can get a good deal on some 6700 10 speed shifters. I know I would need to get a new cassette, but would I also need to get new derailers of brakes? I have Tiagra brakes, 105 front derailer, and an Ultegra derailer (all came on the bike when I bought it). I recently replaced my crank and it would be compatible with the newer group. Thanks for your input!