> You could build ES clusters on AWS directly on EC2 and it would be cheaper than Cloud, unless what you're really looking for is that support contract.
Or you are willing to trade money for dev time. Setting up and running the ES cluster on EC2 will take time and energy (source, I did it ). Whereas setting up the ES cluster on either the Elastic Search hosted service or AWS ElasticSearch is really just clicking some buttons.
However, I'm sure the right solution also depends on the amount of data you are using and the problem you are trying to solve.