There is a similar question on SO but I wanted to add my experience to the question.
I currently have my staging env set up on MongoDB Atlas in Heroku and a local MongoDB (not Atlas) in AWS for my live env.
I know Atlas comes with all kinds of services (like back-ups) that are useful. But for some reason API calls are faster when I do them in live than in staging.
So I'm having second thoughts about switching my live env MongoDB to Atlas.
Is this to be expected (local to be faster than Atlas) or more likely to be just a Heroku issue(free tier on both Heroku and AWS)?