My wife and I had a tour with Markos the first full day we got to Santorini and he really gave us a great tour.
We were a little late in the morning eating breakfast, but he waited for us very patiently. He is very knowledgeable about the history, culture and geography of the island. We learnt so much about not only Santorini, but also about Greece, the rest of Cyclades and the island of Crete. After his guided tour, I felt much more at ease when enjoying different parts of the islands.
Overall, he did a really good job of making my wife and I feel at ease, so we could really enjoy the islands.
Visited September 2014