It handles binary, but not well. http://forum.serverless.com/t/returning-binary-data-jpg-from...

> Ideally long-running requests like that should be rearchitected to return fast and deliver the results asynchronously, right?

Ideally for whom? I can't think of an engineer who wouldn't rather do a simple request/response. It's certainly cheaper than spending the money to keep a connection open longer than 30 seconds, but far from ideal.