My wife is the sparkling wine expert in our family and she likes Chandon Blanc de Noirs.
Chandon is the American line of Domaine Chandon, the famous maker of Dom Perignon. They planted the Domaine Chandon grapes in Napa Valley, CA and produce several very good sparkling wines there. The Blanc de Noirs has a touch of pinot noir grape, which gives it a very slightly sweeter and smoother taste than Brut. If you don't care for the sharp taste of Brut, thy Blanc de Noirs. Chandon also makes a Sparkling Rose, but we haven't tried that yet.