Wet weather SSCX commuter

I have to say, I've had hydraulics on all my mountain bikes for years and they have been a fraction of the trouble of any cable brakes I've had.

Most of the issues people seem to have with cable pull discs originate in not using full length compressionless outers and failing to finish the outers properly after cutting them.

My brakes feel nasty and shreak.

Not sure about the nasty feedback from the brake. Did you bed them in properly as described in the instructions? It's usually a process of repeating moderate sustained braking to a stop down a long gradual descent. The goal is to apply a layer of brake pad to the rotor surface.

Squealing is caused by the pads vibrating. Some people recommend popping a bit of grease between the piston and pad-back to damp the sound. I'm not sure I want free grease that close to my rotors though.

Both of these issues could be caused by alignment. Did you get the mounting post surfaces faced? I notice the TRP brakes don't have the fixings that allow the caliper to pivot slightly to cancel out any imperfections on the post mount.

Contamination is unlikely - that would require a blown seal or some kack-handed workshopery and you'd have not stopping at all added to your list of woes.

Could it** just **be a case of changing the pads / rotors? If so, any recommendations?

Just, just? do you know the price of rotors / pads in this day and age? If you can't get them right throw them back at TRP. But before that, give the rotors a good clean and try bedding them in again.