$10-$20 means low volume. Similar to what you might expect on a small virtual hosting plan. For medium volume, I would happily pay the equivalent of the cost o

$10-$20 means low volume. Similar to what you might expect on a small virtual hosting plan. For medium volume, I would happily pay the equivalent of the cost of 1-2 slices for a managed service. I think a metered plan might be the best option though. There are lots of ways of extracting statistics from a database server. I am a bit unsure how what parameters you would use to meter the plans, but there are lots of metrics you can use. Storage, queries, cpu etc. There are definitely limits for how much you could scale performance wise on something like this, but that isn't even the point. It's about high availability and not having to manage it. If you're at the point where you need a facebook size database cluster for your site, this service probably wouldn't be for you.