I'm a real newbe. Just received my M2 about two weeks ago. It's a fine machine and I'm enjoying it. It was easy to set up and has been printing very well.
I wanted to purchase a dual extruder but that wasn't a choice so I added the upgrade kit in my original order. And this morning I started the tear down / build up for the dual extruder.
All of the mechanical work went very well and I enjoyed doing it. The electronics was also pretty easy although the motor control in E1 (to be consistent with the plug facing the same side as E0) looked like it should go in with the red wire toward the back. On further reading and discovering the block schematics I probably need to turn it around. Now the *big* problem is finishing up the wiring harness or lack thereof on the new motors... The part (wiring bracket) that I was sent does not seem to match the part shown in the pdf. The part in the pdf shows what looks like a fold up back with a couple of holes in it. The part I got is a box with one oblong hole in the back. I'm having a devil of a time understanding how to cram the cables into this box. The connector for the single extruder was elegant, the "box" is not at all elegant. If anyone has some guidance, I'm sort of stuck right now wanting to do this right but ....
So bottom line, I would have loved to have been able to purchase the dual extruder model direct. I understand the comment about learning on one extruder first, but honestly I could have done that with one of the dual extruders. I'm satisfied that I'm doing ok with pla and am anxious to start running pla and petg for multiple reasons. I would have saved some time (and current frustration) if I could have avoided the dual extruder "kit".
Both of my sons have 3d printers and one of them started with twin extruders (not makergear) and had no trouble starting out that way so I'm not convinced that the learning curve is a major barrier.
Finally, I'm completely sold on the quality of the M2 and will definitely recommend it. I'm also very happy about the forum, both with regard to the expertise evident and the openness I see extended to everyone.
Glad to be here
Update: Jules told me today that I had the old instructions for the dual extruder kit installation. The new instructions were completed four days ago and after looking at them I am very pleased. Everything is clear now and I can quickly finish the upgrade. She is also updating all of the other dual extruder materials and said she would have them done this week. All very good news.