Hey!
At Hashnode, we use Mongoose as our ODM. 😄
Personally ... Mongoose is, and has been, my go-to choice whenever I've had to work with MongoDB. Things can get pretty hairy if there are no rules imposed on the data in your database and your database is rather large. Mongoose is the perfect answer to this.
That being said, Siddarthan Sarumathi Pandian is the in-house expert on this topic. Hit him up if you want to have a more in-depth discussion on pros and cons. (He has quite the opinion on this. 😛)