I have both a set for the Pro & Zoom they work well, they even have serrations to help you grip them and have the same dimensions as the stock filters.
I have a set of them for my Mavic 2 Pro. I personally think they are well made and that the optical glass is of decent quality. I have made a little test video shooting using them. The video was shot in dlog m and Dji lut was applied as well as balancing of the exposure but nothing else was altered.