I live for more than five years in Koh Samui Islands. For my part I chose Koh Phangan we surnomons friends "sulphurous" because of the problems posed by the "full moon". I agree with the analysis already done on Samui, but I must add that the traffic is problematic and very dangerous notament motorcycle.one road goes around the island and the real estate explosion in recent years makes it impossible his release, noise polution in Co2 when a clarete the water was goodbye. No reprocessing plant wastewater everything flows into the rivers or the sea and the coral reef, the corals are dying and fish are scarce there.If the sea draws you I advise you Koh Tao, the Meque of diving, or one finds very clear water all year and or the people trying to protect the flora and terrestrial and aquatic wildlife.koh Nanguyang the west of Koh Tao is a view, ban Take affected them a bottle or plastic bag! But life is more expensive, it is relative because it is the same in all the islands to tourists thailand.Samui has its advantages, hyper markets and modern hospitals and "cote d'azurise" However, some of only peaceful ..