It will just need bedding in Poor some water over it and go down a hill holding the brake on, do this about 3 times, and it should improve the performance.
You have more chance brake your bike with maguras, as they but loads of presure on the forks and they snap forks some times. Disks can take a good beatng, as long as you don't totally as$hole them! It stops te frame/forks flexing as much