We just returned from this trip yesterday and our entire family (2 adults and 2 children, age 9 and 13) loved it. Don was an awesome guide - very informative and easy to talk to. He took us up into the rainforest in Manuel Antonio in a vacation buggy (which my son loved!) The highlight is truly the waterfall at the top of the mountain. The setting was stunning and swimming in the waterfall was truly refreshing on such a warm day. Part of our family then ventured onto the suspension bridge for an even more spectacular view (those who were unsure didn't have to make the trip across). On the way back down, we stopped and had lunch prepared at a small local restaurant - wonderful meal. Don then spent extra time at the end of the tour pointing out parts of Manuel Antonio for us to see.
I would certainly recommend this this tour to anyone visiting the area. You are really off the beaten path - not seeing lots of other tours as you are on the way so it is truly unique!