These wines are consistently delicious! Sure they cost, but they have set a standard for American Chardonnay (and Pinot Noir) that is unrivaled. In fact, they have set a standard in the world of chardonnay.
As the noted wine critic Robert Parker has said;
If the Kistler Winery could be magically transported to the middle of Burgundy’s Côte d’Or, it would quickly gain a reputation as glorious as any producer of Burgundy grand crus.
— Robert Parker, The Wine Advocate
I've been on their "list" for more than 10 years and am always happy to make my selections every Spring and Fall. Sure you can buy the wine in stores, but if you want access to every thing they produce you really need to get on the list.