Is the text search on Mongo DB better? For a short while I had the idea to implement database interface using ElasticSearch instead of Mongo/REDIS but the DB design is very much tailored to REDIS and I expect higher effort than using the plugin way..
Background: The story started as I was unhappy with search results and answer was it is limitation in using a simple search library for REDIS (maybe there are others doing better ...). So I could imagine that it behaves better on Mongo. Personally I have no experience with Mongo so I did not consider to use it ...