So far I am really impressed with the blocker's performance,  Very, very few ads have gotten through.

The console offers lots of detail about what was blocked and there is a "cookie" tab that shows what cookies were set with the potential bad or annoying ones flagged in red.  A one-button click deletes all the red ones or there is a button to remove them all.

I'm not seeing any performance hits at all.

The only feature it seems to lack that I would like is a way to right-click a banner ad (several did slip through) and flag it to always be blocked.