I have similar MB for quite a long and while it is not the best possible MB, it is very useful and if you'll manage to grab good quality Cokin filters it could be good option.
The problem with these kind of MB that attach to the lens is that the weight pulls the front part of the lens down. It's harder to focus smoothly and over time you will wear the focus helicals out faster.
Interesting. The one in the video above and the one on ebay show the Cokin P holder as the only mount. Those mount to the lens itself. My friend had one and I used it on an old lens. It didn't turn out well.
Bottom of the hood have two holes and you screw it to support. I got it with some indian camera support wiht rails (what broke already btw, because had been made from bad metal) and MB support had been included.