I am going on a cruise to Europe in 25 days and am trying to finalize and have back up shore excursions. I was wondering what independent tour providers people have used and liked, and which ones to stay away from. I would really love reviews of "Our Explorer" because they seem to have good prices and itinerary so I was thinking about using them. Just for reference I will be going to La Goulette (Tunis); La Valletta (Malta); Messina, Sicily; Rome, Italy; Genoa (Geneva), Italy; Marseille, France; and Barcelona, Spain. Any suggestions on must see places?