The main thing with discs is that they are less susceptible to crap getting in as the contact surface is away from the road. The big disadvantages to me is tha

The main thing with discs is that they are less susceptible to crap getting in as the contact surface is away from the road. The big disadvantages to me is that they get hot which causes the pads to degrade quickly, they weigh more, they're a crap load more expensive and if anything goes snap, hacking it on the road is hard. From a non-technical point of view, I think discs lock up easier and are the force applied versus the braking force isn't as linear meaning less control.