I have been using Divi since it came out, and in fact, actively supported the theme in groups for several years online. As a longtime ET user and continuing Divi and WordPress professional, I feel like I have a real good working knowledge of both. Including the plugins available to use with both.
Divi Extended makes high-quality tools. In short. More precisely, I started with their layouts, heroes….then footers, and headers….then bought a theme. The Hero efforts were great and while I was using them across several sites, they added 20 or 30 more to the product on the ET Marketplace…which I was able to access. Solid.
The theme was really just a purchase saving me money, as it comes with a LOT of extras that are organized to be useful off the site you may be on at the time of purchase. What I mean is, that they provide all the modules separate and organized, allowing for a simpler upload and usage situation. The JSON files are better than much of what you will see, and there are a ton of them.
I would easily place this group at the top of the pile, with groups like Superfly, B3, and the like. And they are cheaper. Quality and price are solid, you can’t go wrong using the products they offer.