In my opinion, the popcorning and the belt sliding are the very down sides of Versalab M3, I use it for three months, every time to use the grinder, these two "defects" made me disappointed. I have to pick up coffee beans from the floor if I do not use my hand to cover the upper funnel while grinding, and I have to pour the coffee bean slowly. Other grinder no need to worry this matter, they have time to prepare other pre-brewing procedures etc.
Regarding the new funnel cover, I would say the Versalab treat it as optional accessory is wrong, moreover, the design of this transparent cover is too simple, no aesthetic sense to match the design of the grinder. Remember, it is a 3,000 US dollar grinder ! Not a cheap one !
Versalab has a responsibility to upgrade the belt sliding problem for the customer, actually it is not upgrade, it is a remedy.