On the CONS: this extension costs $$ to unlock all its features.
On the PROS: if you have multiple interests or lots of channels; this is EXCELLENT! And totally needed to organize your many feeds.

Great extension.
Expect it to get even better in the future.
Youtube would not be the same without your extensions for managing subscriptions and playlists.
Thank you very much for your work, providing the functionality Youtube should natively provide ( but doesn't, only god knows why ! )