This model was an absolute lifesaver! I was tearing my hair out trying to figure out why I was having feed problems with the AMS. Replaced all the PTFE tubes multiple times, tore down, thoroughly cleaned, and rebuilt the toolhead (replacing the extruder gears for good measure), and finally went after the AMS Active Extrusion Wheel. Lo and behold, a chunk of the cap falls out once I get the Internal Hub Unit detached from the frame. Thought I was going to have to buy a whole new Hub Unit, but OF COURSE this community has solved this issue already. A quick print in ABS from the manual feed (the first time I've not used the AMS with my machine) and I was back in business!