I’ve been testing the cleantalk plugin (from https://cleantalk.org) for just over a month at several sites, and I must say that I’m firmly impressed by the plugin.
The spam protection is extensive, covering all parts of the site, including registration forms, comments forms, contact forms custom contact forms, and also features a spam firewall.
So I’ve disabled all the other anti-spam plugins that I’ve tried – and that’s not to say they don’t work, but cleantalk does the job of several plugins which only covered for example comments or user signups.
And I’ve had literally zero spam, in comments, registrations, or contact requests, since I installed it. The analytics are easy to access too, with a full breakdown of every request they processed, with the remote IP, request details, and whether it was approved or blocked.
So it’s fully featured, but with no bloat or annoying popups in the dashboard.
10/10 all round!