I haven't come across the particular chain punching video discussed, only one which is basically a marketing teaser, but I did look through a few of his other Youtube videos.
In short, he appears to be a pretty competent Wing Chun practitioner with plenty of striking power and technical understanding. His instructional style is also quite competent. The best MA instructor or Wing Chun practitioner I've ever seen? No, but pretty good and a long way from the worst. Refreshingly free of the "MMA is the spawn of the devil", "Everyone else is a moron except me and my teachers and buddies, especially YOU", and "None of you know what I know and I MIGHT tell you a BIT of it if you kiss my a$$ for an extended period" attitudes.
He's obviously put in a lot of time and world travel seeking knowledge, and put out a significant amount of material. It seems a bit overpriced to me in comparison to other instructionals, but not enormously so.
It's easy to take cheap shots at someone who puts himself in the public eye so much and seeks out so many instructors, but I think that's inappropriate. Not everyone has the ability, desire, or willingness to make sacrifices to do that. Good luck to him, he's doing more than most to publicise Wing Chun and try and keep it relevant in the current day and age.
