Prints started to get all wonky about a week ago. I couldn’t figure out the problem. Changed the nozzle, tighten the belts, lubed the z screws, and cleaned the carbon fiber rods. Disassembled the extruder and I didn’t see any clogging, but when I disassembled the hall sensor, I noticed a lot of wear. Then I found a piece of metal inside the extruder that I suspect broke off from the hall sensor somehow. A new extruder arrived yesterday and the X1C is printing like a champ again.
I had a look too, and they seemed quite affordable. At the risk of sounding pessimistic, :) I think the biggest risk is that they lower quality and raise prices once they get big enough, but hopefully there will be high quality 3rd party parts available by then.