This to me is key, it blows my mind how often people bring their brakes into the shop and complain about them not working but they could not be set up any worse if I tried. The biggest thing I see is people pulling the cable so tight that the brake are doesn't have any travel left. People need to realize mechanical discs are not hard to set up but you do not do everything just like with v-brakes. A little research goes a long way.

I have a set of Tektro mechanical disc brakes and they are by no means high end and even they have loads of stopping power and are super easy to adjust.