The Brother's Restaurant at Mattei's Tavern is not the overall best restaurant you may ever eat at, but it's certainly the best in the Santa Ynez Valley, and more importantly, the Prime Fillet is one of the best pieces of meat you'll ever eat (It really is that good). The setting is nice (a very old Inn-type establishment), the wine-list is excellent as expected in Los Olivos, and the service is friendly and good, but all of these positives pale in comparison to the Prime Fillet. \r
Now, with that said, the rest of the food at Mattei's is excellent, just not worth raving about to quite the same degree. If you take a trip to the Santa Ynez Valley, please eat here, as everyone I've taken agrees that the restaurant is at least excellent, if not one of the best meals they've had in a very long time.
Pros: Best Prime Fillet Ever
Cons: None really - price is good, setting is nice, service is good.