Mike, thank you for sharing the article. That can be a very popular plugin for X-Cart 5
But we think it is better to stick with a service like Akismet that improves their anti-spam technology every day and fights with constantly developing spam bots.
$5/mo is not a big deal IMHO to fight with spam and not to have a burden of updating your anti-spam software regularly. A service like Akismet will do the job for you while all you need to have is an integration with them.
What do you think?