Maybe the driver is a good idea, not just for the wine but also as some wineries are not at all easy to find for an outsider.

I have visited Bodega La Rural on a Saturday and Bodegas Salentein on a Sunday last year. No problem, they had tours a.m. without prior notice. Found La Rural the more interesting one, and enjoyed lunch at the nearby Casa del Campo. The Trumpeter Shiraz-Malbec they produce must be one of the wines with the best price-quality relations in the whole world.