Great extension. I use it to download tutorials in 720p quality, so I can play them offline - which is much faster for scrubbing timeline than online streamed videos.

I've tried many youtube download extensions and this is the best. I think it's worth donating a few dollars to the plugin author, since it does require work to keep up with code changes on Youtube's side. If I ever need 1080p downloads, I will happily buy the pro version.