I highly recommend Cline and their sister winery across the way, Jacuzzi. Go for the Cline Mourvedre and Jacuzzi Primativo. I can't disagree more with Mikester...we went to Roche in Dec. 2010 and the wine varied from mediocre to just plain bad, but was made hilarious by the tasting room carnival barker who rudely gathered everyone around for barrel tastings and tried to boast about this nasty juice being the best Pinot noir they've ever made and we should all buy futures. Big waste of time! Now me and my wine traveling party have a saying: "Roche is Roach!" and when we've gone on further wine trips the worst wineries contend for our nomination of the "Roach winery"! ....we also went to Buena Vista--historic winery, nice scenery, decent wines, ALL way overpriced for the value.
If you have the time, concentrate your trip on getting further up north and spend more time in the Russian River Valley and environs. Dutton Estate and Thumbprint Cellars for sure!!