We did a tour of the Curi Cancha Refuge with Marcos at the recommendation of Reina at Cabanas Valle Campanas and he was a wonderful guide. We saw all sorts of wildlife and he took great pictures through his scope with our camera. He spotted four quetzals and tracked down a bell bird as well. As others have mentioned, he was knowledgeable, pleasant, and clearly is very passionate about what he does. Highly recommended - it was a great way to spend a morning!