It works well, the points system is interesting, it doesn't keep blocking all sites madly. But it has some annoying problems, sometimes it starts blocking any website, then you have to uninstall and install again; the extension has for some reason quotes and commas set to block, so if a page has that, the extension will score and maybe block the page (And I didn't find where they are, so I don't know how to solve it.)

It is working fine, but add a site to whitelist can be more easy. Have to type site address in the preferences is very work, could be a button in toolbar to add to whitelist. Another suggestion is a option to define a address to redirect for another site when block.