I've been running Manticore (previously SphinxSearch) on a faceted search heavy site with a million MAUs for 15 years. I'd definitely use it again for another project.

If the data that you want to search is entirely contained in a SQL database, it's an uncomplicated and powerful solution, definitely check it out. If not, Manticore may still be a nice solution for you, but I can't speak to that.