Shameless plug: if you want something almost as cheap but without having to drop the ability to subscribe from all client libs (not just js), queryable history,

Shameless plug: if you want something almost as cheap but without having to drop the ability to subscribe from all client libs (not just js), queryable history, presence, connection state recovery, webhooks, stats, firehose to queues, etc, then have a look at https://ably.io https://ably.io. (disclaimer: I work there)