The brass inserts for PTFE were missing but I found different parts with thread online and printed them.
The blades that came with the kit don't fit. That's just a minor issue since you can just use standard blades from a cutter knife. More of a problem was the 5 pin cable that connects the mmu with the einsy board. Original Prusa has just 4 out of 5 wires connected. The cable that came with the unit has 5 cables. You have to remove one of the unnessecary white cables and you need to repin on one side because the pin layout of the cable is wrong. If you don't get your mmu recognized by the printer this will be most likely your problem. Took me like 4 hours to realize whats wrong. A note in the product description would help a lot on that issue. Besides that I can recommend the kit. I printed all the parts on my own because I wanted precise parts. I didn't printed something yet but I'm confident to get the unit working as it should.