Ranked in these QuestionsQuestion Ranking
Pro All Elasticsearch features are supported
Pro Includes S3 bucket for snapshot and restore
Pro Allow uploading custom plugins
Pro Dedicated clusters with reserved memory and storage
Clusters aren't shared, customers get their own dedicated cluster. Memory and storage is reserved - there's no upper limit in terms of indexes or documents to be stored - and Linux containers are used (LXC) for and process and resource isolation, which means you get the memory you are paying for without having to compete for it with other customers.
Pro Supports cjk plugins
Pro Comes with Shield (security), Watcher (alerting) and Marvel (monitoring)
Pro Extremely stable
This is the official version of hosted ElasticSearch and it's backed by the ElasticSearch developers. This makes it probably the best in terms of stability as far as services that use ElasticSearch as a backend go.
Pro Allows multiple types of documents per index
Another useful and unique feature to Elasticsearch is the ability to have multiple types of documents in a single index. You can then facet, query or filter against all document types or a single type.
Pro Free trial available
There's a 14 days-long trial available without any credit card required.
Rather than pricing by number of documents or API calls, they price by instance size. So if you have a lot of documents (>100k) that are very small (50MB), or a large number of shards which are small, you won't be arbitrarily forced into a higher pricing tier. Same deal with number of requests - if you need more memory on your instance, then upgrade. If you have a lot of very fast requests, you can stay on a lower tier.
Pro Easy to work with
Elasticsearch gained its popularity amongst developers by being enjoyable to use. A simple feature comparison against it's competition doesn't convey the significant advantages of just how easy it is to work with. This is due to multiple design choices such as the use of JSON for the API and queries.
Typically 0.5-3x the cost of other providers.