Does the greeting matter all that much? “Dear Ms. Reid” seems too formal and “Dear Janet” feels the opposite. Is “Dear Janet Reid” okay or does that give the impression of a mass query?
Anything that has my name on it doesn't feel like a mass query. Look, I know you're querying everyone under the sun. I'm ok with that. What doesn't work is "Dear Agent" or "To Whom It May Concern" or no salutation at all.
Dear Janet is fine. Dear Ms Reid is fine. Dear Janet Read, not my fave, but ok, what the hell. Dear Snookums works too, but probably not the best choice. And don't think I haven't signed and sold books that arrived on queries with Dear Barbara Poelle. Yes indeed I have.
Use the salutation that feels right to you. You're not going to go wrong with my name, whatever form it takes.
Janet Reid, QOTKU