I’ve used aluminum brazing rods which are basically the same thing. The guy in the video is calling them welding rods but he’s really just brazing. They work but it really depends on the project you’re working on.
I’ve seen that video before and almost ordered some just to see how they work compared to the brazing rods I get locally. I don’t really braze aluminum much anymore. I usually just tig weld it. They have cheap tig welders capable of welding aluminum for less than $300 but I don’t know how well they work. Aluminum brazing rods definitely have their place though.