Elasticsearch 5.x as nosql datastore

I currently have a site with mongodb as nosql and elasticsearch datastore activating search functionality. Data are more or less duplicated from mongodb to elasticsearch. I have to update the search code as it still works on a very old version of elasticsearch.

In the process, I found that elasticsearch in its latest iteration is already much closer to the nosql datastore than before.

From a perspective:

• My data is mostly readable, few updates
• Data have documents with attached documents
• I am using geoindexes in mongo, I would like to add geoinformation to elasticsearch in the future.

Does anyone have a current version of Elasticsearch as a nosql datastore in production? I just found very outdated information covering elasticsearch version 1.5 and earlier. From the documentation ( https://www.elastic.co/guide/en/elasticsearch/resiliency/current/index.html ) I see that many issues have been fixed in version 2.0 and 5.0.

Can someone with understanding and experience with version 5.x give recommendations?

Thank!