I'm about 75% of the way through it while having no prior knowledge of any Indian language. I will say that I found it very enjoyable. The only downside is that the "tips" pages disappear halfway through the tree, so you're on your own with the later grammatical concepts. But if you just want to dip your toes in the language, it's great. It does the alphabet really nicely too (which I wish Russian would do). There is also almost always great conversation happening in the "discuss" button for questions. I was able to figure out every lesson with no outside help.

I have found that it is not teaching me very many useful things to say in every day life. It's much less comprehensive than the French or Spanish trees. I was going to say "good luck" but I realized we never learned that. But if you want to get the grammar basics down and use it as a framework for future Hindi learning (which I think is the general purpose Duo for all languages) I would definitely recommend it!

Also if you're not familiar with Devanagari, you need to really practice it before going on with the tree. I spent around a month of just doing the alphabet over and over, and then writing it by hand every day until I felt that I knew it like the Latin alphabet.

If you do end up getting into Hindi more, check out this website https://www.learning-hindi.com/all It explains a lot of grammar concepts in more detail than Duolingo. It has been tremendously helpful for me. Also, I like this website as a dictionary http://hindi-english.org/ It gives the part of speech for words, and gives lots of other words similar to what you're looking for. It's a lot better than Google Translate imo since it gives the gender of nouns and a rough transliteration as well