My name is XXXXX XXXXX X am a General Expert. I would love to give you my answer based on personal opinion and past experience working in a department store men's department during my college years, long ago.
I live in Florida and have had to purchase Dress Shirts for my husband and son and have found that a good cotton and polyester blend holds up well in the sub tropical type climate of Fl., where heat and humidity are big factors and can affect the clothes that are worn. The cotton allows the material to breathe and the polyester helps keep the shirts looking fresh and neat for a long day. The cotton shirt alone in a tropical climate will stretch, wrinkle and look poorly after a day of wearing it, where as a cotton blend holds its shape and will look good throughout the day even with warm or humid weather. Again this is based on personal experience, since the decision would have to be by the individual wearing the shirt. I hope this information is what you are looking for. Please let me know if you need further clarification or have a follow up question, by hitting reply. Joan