It's so hard to say "good buy"

What is a "good buy"? Ideally, you would think inexpensive. Unfortunately for my wallet, that isn't the case. A good buy means good value. Pricey or cheap, but worth every penny. But isn't that subjective? One of my favorite wines is Cline's Mourvedre. Cline Cellars, known for their "ancient vines", has resurrected or preserved the Mourvedre grape in California. Mourvedre is a key grape in France's renowned Chateauneuf-du-pape (which I've actually never had and am dying to try). But I looooove Mourvedre. It is rich and earthy with plum flavors, pairs well with herbed meats and dark chocolate, phenomenal with lamb roasted with Herbes de Provence. But back to the question at hand, is a good buy in the eye (or tongue) of the beholder? I love Cline's Mourvedre and the cheapest I've found it for is maybe $13 and locally for about $16. Okay, not a fortune for your standard wine connoisseur. But for a struggling twenty-something, it's more than should be invested in your average weeknight wine. I would classify it as a good buy - more than I should spend, but worth every penny. Perhaps it is the psych-major in me resurfacing, but it is it a good value because it is a great wine? Or is it a good value just because I like it? Who makes the call on what is a good buy? Something to think about... over a good glass of wine.