[annnnd]

> ...instance in AWS, and it's a pain to use Mongo there

Why is that?

Quick google search doesn't hint at problems, but rather at pretty slick marketing pages: (which doesn't mean much, I know) https://aws.amazon.com/blogs/aws/mongodb-on-the-aws-cloud-ne...

[cwmma]

It's more then Postgres is so easy to use there with RDS which does all the setup for you.

[rspeer]

Running MongoDB effectively on AWS is very expensive. It's the opposite of what AWS is optimized for. It requires a dedicated amount of RAM that scales with your database, and it requires permanent storage that's about 100x the size of the actual data.

It's very much unlike a nice, bursty, CPU-bound web server.

Also, you can't use the big selling point of AWS, which is that you can scale it "elastically". Okay, you could, but it would be a terrible experience with lots of unavailability.