This tour was not as advertised. We are experienced travelers who have booked through Viator before and been most satisfied. The tour description led us to believe we would learn about the Duoro River valley. Our driver, Carla, provided no information other than a few brief sentences, like there are 4 kinds of port - red, tawny, rose and white: those are grapes for green wine they look different than other grape vines and in my opinion the views between Pinhao and Regua are the best. She told us nothing about the river itself, no tidbits of interesting information. We were not expecting nor did we want a non-stop monologue but we were expecting information with some substance at various parts of the tour. The van was extremely dirty. You could see where windshield wipers had been used - the area cleared by the wipers was covered with bugs and the area outside the wipers' reach was so dirty you couldn't see through it. The side windows for our scenic tour were very dirty also. The air-conditioning in the van was not working properly. It wasn't too bad in the morning as we were driving to the Douro but, after the first wine tasting stop, the three of us in the back seat were sweating profusely. It is really miserable. Comments made by Carla made it clear that the company knew the van was not up to par, especially the air-conditioning. We told her that, if the company knew there was a problem, they should have told us when they picked us up and given us the opportunity to opt out - we would have - we came from Florida and part of our motivation was to get away from the heat! We thought the tour was going to be in English - and it was. But it was also in French as one of the three couples spoke only French. So we had to stand and listen to everything twice. Carla was a good driver. The wine tastings, which Carla was not around for, were fine - one OK and one outstanding. The boat ride was pleasant. But the overall experience was really spoiled by the dirty van, the HOT van, and the lack of interesting information about the Duoro Valley. We definitely did not feel we got our money's worth. Our standard practice is to tip very generously. We did not tip Carla and neither did the other two couples on the same tour. One of the other couples said they had been on previous Douro Valley tours and learned a lot - and felt there were many interesting things Carla could have told us. Thank you for listening. We very much enjoyed our Mallorca walking tour and Porto walking tour through Viator on our same trip.