We don't like the current Cleantalk plugin at all so we've switched to the Cleantalk API version and coded our own antispam plugin, FV Antispam Pro. Cleantalk were kind enough to add the features we liked (managing blacklisting from within WordPress) but with very poor user experience.
What we didn't like is how Cleantalk's plugin takes over the whole comment interface and is really ugly. It's a pity. Fortunately, FV Antispam Pro gives you the power of Cleantalk Antispam blocking within a well-designed native WordPress plugin.
The way FV Antispam Pro works is that filtration is built in three tiers:
- Tier one is machine spam filtration. This gets rid of what can be tens of thousands of bot requests. Only sophisticated bots and manual spammers get past the machine spam filters. Bot comments get sent straight to trash.
- Tier two is Cleantalk. We send each comment who passed bot filtration to Cleantalk's API to check both IP and email. If a comment fails Cleantalk's test it gets sent into the Moderation queue.
- Tier three is Akismet. Optionally you can send each comment which has passed Cleantalk's checks to Akismet for checking. Akismet has more false positives than other services so for some sites you may wish to disable the Akismet checking.
Why not just use Akismet? Automattic monitors usage of Akismet quite closely. Akismet Plus is €59/year per site and has a limit of 75,000 checks per month. An enterprise license allows unlimited sites but only allows 100,000 spam checks per month. This can get very expensive. With FV Antispam Pro you can use either free Akismet (Automattic doesn't monitor low usage sites) or safely use one of the paid licenses without taking the risk of being charged big money for high volume usage. This can save you thousands of dollars per year.
FV Antispam Pro is fair to Automattic as when you are sending fewer checks, their servers have to work less hard.
Cleantalk database API costs are $3 for 10,000 checks/month (enough for a few small sites with FV Antispam Pro), $11/month for 50,000 checks (enough for about ten sites, including a couple of busy ones) or $33/month (enough for about fifty sites including about five busy ones). So it's very affordable. You can buy a year at a time.