Some enterprise production questions:

* Is it HA? What HA topology is it designed for? * How many messages-per-second can it ingest? * What about with multiple clients? * Can you front-end it via a load balancer? * Can it guarantee only-one delivery? * How does it handle errors? ie: when a message is retrieved by a client and the client errors after the server dies, what happens to the message - does it redrive or expire correctly when the server comes back up? * How does it guarantee consistency in a multi-node environment? * How dies it behave when a node dies/runs out of memory? * How do you monitor it? * How do you recover a corrupted instance? * what happens if/when the SQLite partition runs out of space?

etc etc.

I use SQS as a main pipeline, and I would want to know a bunch of these things before I'd even consider replacing it. But for someone with one box on a VPS somewhere, you probably only care if it runs for a year without crashing