I don't like the roller style spool holder come with the Prusa MK3 MMU2.
So I made a hanging type with 3d printed parts and the original bearings and rods.
This is my own project to fit my situation. I hope it can help some of you.
I mainly use filament from eSun and Sunlu. I think it fits most standard size 1kg spools. Bigger and wider spools will not fit though.
My setup can shorten the distance between the printer and the spools and solve the problem of the crazy retraction loops.
Please see printing settings and post-printing for details.