Simple review
Should I get Grammarly?
The free account of Grammarly mainly correct spelling mistakes and some punctuation, but that is it. The good part is that it explains to you what is wrong, why, and it gives you options. The annoying part is that it gives you a list (big in my case) off all the other mistakes that they see in the text but that they don’t cover with the free Grammarly account (e.g., wordy sentence, style problems, incorrect use of the phrase, etc.) and it let you wonder; what did I do wrong?
Considering the above, I decided to purchase the premium account of Grammarly to check it out; and it is better. It won´t give you all the answers and correct the full text itself as I was expecting, but it will help you to check the general grammar, clarity and it will help you recognize what are your main problems in English and fix it. In my case, wordy sentences and excessive use of passive voice.
So, should I get Grammarly? Overall, I think Grammarly is a useful tool, but I would not use it as the only way to check what I have written. What I usually do (if English is not your native language) is to translate the text in English to my original language using google translate (it is good, at least for Spanish). If it all makes sense, then, I will use Grammarly to check the small details.