This a GREAT addon, with excellent functionality.
My main problem, after using if for year or so (and not working for a while, now fixed), is that it slows down Youtube page loads to a crawl.
I´ve even tried moving my entire Youtube profile to a Ramdisk, to maximize speeds, and more often than not, I still get a top bar telling me "This addon is slowing down your browser", or something like that.
If you manage to make this FASTER, and more capable of reading hundreds/thousands of blocked channels, an addon worth paying for, indeed.
Cheers!