I expect there's going to be a lot of LANDR nay-saying.
Myself, I've tried it out from curiosity a few times, and hopefully without sounding to arrogant, it doesn't do anything I can't do better myself. So not a fan as such.
However, if it helps some people get their stuff where they need it to be, then I'm all for it. It's not nearly as good as good mastering, nowhere close. But it's better than a lot of bad mastering I've heard.