My Take
Overall, I like it and I recommend it. Just be wary of using it exclusively, or of your ENL students getting addicted to it!
How I Use It
I use the website translate.google.com when a student says a single word that I don't understand and I need a direct translation. For longer translations, I have been told by native speakers of other languages that Google often misunderstands context and uses the wrong definition of a word, hindering understanding. When my newest arrivals of ELLs use Google to translate their work into English, I am often confused by what they are trying to say. It works ok for a single word, or a sentence. But not with a paragraph or an essay.
All of my students have chromebooks that they use in class. I have encouraged them to download the Google Translate extension to chrome because they can use it to toggle back and forth between language. So if they don't understand the directions on Google classroom (or elsewhere) instead of copying and pasting, the extension will translate the entire page - saving a ton of time!