I only use the CAPTCHA on new registrations with Stop Forum Spam set to "auto with message"; the only spammers that get through are actual humans, and it's very rare.
If you opt to insert an API key from Stop Forum Spam you can submit users to the database and track how many users you submit through their site.
Stop Forum Spam not only blocks spammers during registration, but it will also check against their database when the login page is accessed, so if someone gets a registration through before being added to the database, it'll get them again if they've been added since the registration.
So, if someone gets thru CAPTCHA and their Email and IP are good they get through?
What happens if they have a Bad IP or Email?
