As for the pros or plus sides to making reservations for a guided wine tour, you will find that there are a number of them. Perhaps, the most influential one is that you automatically have a designated driver. This is an important factor that many do not take into consideration right away. For many individuals, a few sips of wine here and there can quickly add up. This is not an issue that you will have to worry about with a guided wine tour, as most companies will provide travel arrangements for you, like in a small bus or van.
There were many wineries along the Russian River that we did not need a reservation for. Our Bodega Bay Vacation Rentals owner was very helpful in educating us about this.