Integrity Pro builds on Integrity Plus. It has the new crawling engine, it checks links and generates a sitemap with all the searching, filtering and exporting functionality of the Plus version. It adds SEO details and a sitewide spellcheck. It isn't intended to replace Scrutiny, but to be pitched between Integrity Plus and Scrutiny, a more affordable step for Integrity Plus users. There is, of course, an upgrade from Integrity Plus.