Works perfect with WP 3.5.1
Deletes all data, but author has already warned about it. Besides, this ought to be used just for pure testing.
One more thing; in a multisite, the plugin generates data on all sites when it is activated form any particular site (and not just from the primary site). A bit awkward, but then its just for testing anyway.
If functionality for deleting only the generated data + option for site specific or multiple sites in Multisite are introduced, its worth 5 stars!