we're[0] using pgvector via supabase in prod and we've had 0 issues. We store things like the natural language explanation of what a SQL statement does and use pgvector to look up the SQL based on a users new natural language question.
I think the argument against pgvector would be "it doesn't scale", but we're using it against hundreds of thousands of rows of data and the performance is solid (< 100ms). Maybe we'll run into issues with tens of millions of rows, but we'll worry about that when it actually becomes a problem.