Reasons I immediately disabled this plugin:
1. Creates an two entirely new menus to the left navigation area, which is absolutely unnecessary for such a simple feature addition. Particularly the YITH menu item shouldn't be added, but even the Size Charts item should just be a sub-menu of Woocommerce.
2. Adds advertisements to the plugin's settings page, but even worse it adds 7 CSS files that load on every page of wp-admin.
3. Wasn't exactly intuitive. I don't believe it should be necessary to read lengthy (and confusing - seems to imply you need a license key) documentation to utilize something like this.
4. Adds an entirely new CSS file just for this plugin. And, it adds it whether you use the size chart on a product or not. And it adds it to all pages, not just Woocommerce product pages. Your entire site's performance shouldn't have to suffer just because you want a size chart somewhere on a product page. 🙁
My rating is based on losing 1 star for each of the above issues.