Was a lot better a few months ago, before they added a bunch of advertising built into the YT interface that you CANT remove, as well as being unable to disable a few of this addons additional toolbars and stuff that clutter the screen.
I have been using this addon for years and I love it. Every OS I install on my desktop/laptop has this with it. It has gotten to the point that when I open up youtube on my friends computer my eyes squint because it isn't the lights off mode that you provide. I also want to say that the repeat option is the best part of this app. It helps me fall asleep, enjoy analyzing music and just makes my life easier.
Excellent! Having tried a number of other YouTube extensions I'm happy to say I like this a lot. Would like some more settings for the mouse wheel volume, like size of font and perhaps transparency options.