Faster than both Rehike and Polymer, very functional, brings back lots of features that are gone from current YouTube, while having the ability to use a few modern features like Community posts.
There's a few minor gripes I have, like how some caption formats don't display properly and how theres no end screens, although those would probably be hard to implement so it's no big deal.
Some of the links are broken which is a bit of a bother but its not dealbreaking, and I legitimately like browsing on V3 more than I like browsing on the actual YouTube layout. Would recommend to anyone who's feeling nostalgic, hates modern YouTube, or finds the current layout slow.