I just installed the plugin, and it's not more than a sales counter to sell you a service.
It even goes beyond "the mechanic telling you to change stuff which is fine" (normal for virus-scanner software).
The buttons for "view what is different" on the fake scan results for a plugin marked as "DIFFERENT THAN THE VERSION IN REPOSITORY!" doesn't even take you anywhere.
I took the task to find the repository for the exact version (Akismet 2.2.7) and compared it myself with the version in my site, and THEY ARE IDENTICAL. Byte by byte.
Other features other than "SCAN AND LIE TO ME" or "UPGRADE" don't work either. It just takes you to a not found page.
My site IS infected with some spamming code, and this didn't even found it in my theme files.
Again, this is just a useless window to sell you something you might even not need, based on terror.