The pricing needs to be more clear. For example we run MYSQL RDS in production with two AZ enabled, we pay x2 the prices.... so if its only costs a bit more than MYSQL RDS and you get 3 AZ for the same price -- this is good. Moreover, there are costs that come with storage (database size), this thing seems to be smart about being more efficient with allocating space.
As i understood this your database storage is replicated to multiple places, but it still runs on one instance. It does not have failover to those replicated places. You'll have to launch multiple instances for that just like RDS. So cheaper, no.
