I'm planning a trip to Napa/Sonoma for four days in April to celebrate a big birthday. We're staying in Carneros, and I'm still developing my list of must-visit vineyards. I want to schedule at least one in depth tour and tasting, and would love recommendations for ones that will give my husband and I a really special experience. I've researched Cline and Iron Horse, and both seem great. This is our first time to the region, and we like all kinds of wine.