I’m currently using Minna no Nihongo! I went into it as an absolute beginner (well, I memorized hiragana and katakana and had about 5 levels on WK and had watched several dozen episodes of Japanese Ammo with Misa’s absolute beginners playlist, but I’ve never had formal instruction and had never attempted self-study before then), and so far, I have had absolutely no trouble following the textbook. I’m only on lesson 5, so I suppose this could change in the future, but it’s not difficult at all to use as a self-learner if you’re very dedicated and you work well with textbooks.
My process is to pre-learn the vocab, then once I’m comfortable with it (I add the chapter’s vocab to my Anki deck and go through it each day until I know it), I read the grammar section in the translation book, then set the translation book aside and read the lesson in the main textbook and attempt to do all of the exercises in the book and in both of the workbooks that I own (I don’t own any of the other supplemental resources, just two of the workbooks) without consulting the English text. It works really well, and I don’t have to do any flipping back and forth between the main textbook and the translation book. It feels awesome to be able to read the book in Japanese, and it’s satisfying to be able to read without looking anything up!
That said, if I do run into any confusing grammar points, I have other resources on hand to help out, such as A Dictionary of Basic Japanese Grammar, and I’ve also watched enough Japanese Ammo with Misa that I have a basic understanding of the plain form of verbs as well as the ます form, and other things about informal grammar that my textbook has not yet taught. I’m basically treating the book as practice for approaching native materials, with a plan of starting to read graded readers and then manga once I get further along.
The various supplemental books and audio/reading practice are supposedly pretty handy if you can afford them, according to reviews I’ve heard from others. It all gives you further opportunities to drill the knowledge that you’re learning in the textbook. Using all of them at once would be pretty in depth study and would take a fair amount of time, but if you managed to complete it, you’d probably come out of it with a very solid understanding of the material that the book teaches.
There are some aspects that I’ve heard that it teaches more than others (polite speech over casual speech, for example), but honestly you need to learn both anyway, and you can get practice with the other grammar from other sources and ideally native media once you have a strong enough foundation of grammar and vocabulary to begin to look beyond the textbook.
A lot of people hate textbooks in general and hate MNN specifically, but if you’ve had success with textbook study in the past and are very dedicated, I think you would probably do fine with this one. I know that it’s very doable to learn on your own from it. And if you do happen to get stuck, there are plenty of people on the forum who could try to explain things for you or point you in the direction of additional resources to clarify things that you find to be confusing.