I absolutely love this add-on. The vanilla aesthetics of YouTube are awful, and this offers a great amount of customization options. YouTube now looks and functions exactly how I need it to, and I can disable YouTube's pesky novelty features for a much more controlled experience.

My only complaint is that the Enhancer toolbar now displays incorrectly. The buttons don't display within the borders; they pop out of the top and it hurt the aesthetics. Still functions perfectly though, so it's a minor complaint.