I have read that it is as important to use a quality vermouth as it is to use a quality gin. That having been said here in Springfield Missouri it's all either Gallo Vermouth or Martini & Rossi with M&R being the slightly more expensive. Let's face it...vermouth has one use ordained by The Lord and it's the lower half of a Martini. I think you're fine.
Okay, well at least it’s good to know I’m not alone in having limited vermouth options.