I would think the biggest braking bang per buck would be to upgrade the rear calipers and disks being that they are only a single piston? Possibly upgrading to better pads and checking out vented/drilled/slotted rotors. I love the looks of the AMG calipers popping through the wheels so from an appearance stand point I would consider them but I'm not spending 2k on brakes just for the looks... Call me cheap or what have you but I would rather see a new set of forks on my mountain bike for that kinda money.