The cron event this plugin creates overloaded the cron schedule and drastically spiked our server load.
I only had this plugin installed for a few days and removed it after not seeing much of a different with our database load. I then noticed a spike of CPU usage on our server, and noted it was coming from our cron files (I run a multisite). This was because of 100+ instances of an hourly event. Here is the line of code I noted as being the cause.
add_action('clean_cache_event', array(&$this, 'hourly_clean'));
This is being run way too many times, and not removed during uninstall. At the very least this needs to be changed to a one-off event if it is going to keep adding to the site.