Our guide was only fair. Lots of talk, but not much substance.
My only problem that I had was...SPENT TOO MUCH MONEY!!! :-)
This was a wonderful day, spent with a small group of people and a fantastic guide Don, who had arranged some really interesting places for us to visit, and taste a variety of wines from Napa and Sonoma Valleys. Cannot recommend more highly. Visitors from overseas should be prepared though for higher than anticipated tasting costs.