ElasticSearch is very easy to use for those who have basic knowledge of SQL database like MySQL or PostgreSQL. It has good integration with other tools such as Kibana, Grafana etc which makes it more powerful than Solr. I would say that there are some things in ES which can be improved but nothing major so far. If you want an open source tool which will help you store data from different sources then go ahead using this product. We had problems storing our application logs along side the normal web log files. We were able to solve this problem by integrating ES into our system. I like that we can use it to build our own complex solutions without having too much headache with integration, but also being able to scale when needed is really important for us! It's not so easy sometimes find good documentation about how things are supposed work because they changed some of their APIs in recent updates. We used this product mainly during development phase while building new features or improving existing ones using ElasticSearch API (we have almost 20 different projects).