From the Typesense's site: "Typesense is an in-memory datastore", "If your dataset size is 1GB, you'd need between 2GB - 3GB RAM to hold the whole index in memory."

Manticore is different in terms of this, especially the Manticore columnar storage which doesn't require a significant portion of the data set to be stored in memory. This allows, for example, for a 1TB data set to be served on a standard server with some 32GB of RAM.

In my opinion, the main difference is the history: this search engine has been used for 2 decades in various production sites.

Mantiscore is an opensource fork of Sphinx Search, which released its first version in 2001. The fork started after the latter went from opensource to proprietary, at the end of 2017. The engine is stable and battle-tested. IIRC, Craiglist uses Sphinx.