The more and more I look at this extruder, the more I like it. It's very compact, and would be very simple to adapt to my hotend mount. But apparently, the gears they use are proprietary made from pinion rods (no add. specs given). The bearings are 5x10x4mm I think, definitely a 5mm ID RC car bearing. I have a bunch of those, so I'll test fit out later this week. I really need to get this dual extruder thing going fast though. I have until mid-december to finish designing and print AND ship 100 almost life-size hands, along with 50 business cards which I still have to design and print. So important, guess these are going out to some big names in euro art scene, could be a career changer here.