Even if he mentioned a product by name, as long as he isn't associated with the product and he is simply endorcing something that has worked for him, it's legal here.

As for Youtube, even if, or should I say ESPECIALLY if he is associated with a product, it's legal to post how tos. I've given several companies business because they had a video that showed me how to use their product and that their product would work for me. Isn't that the real value of Youtube?