That video on the page looks kinda sketchy. As mentioned, those corals are all fake. And IMO, those fish in the tank look like black mollies, which are freshwater fish.... :/
Now as for the quality of Zetlight.... I don't think it's too bad. I personally don't use them, but you should definitely get into contact with Fred (his username is oyf709). He (used to?) sell the units, and speaks pretty good of them. I think now he carries different LED units though. Here are some pictures of the Zetlight that he sent me a couple weeks back:
