Last batch of tshirts I had made were a 50/50 blend. My opinion was that they made you sweat more, didnt breathe well, and would cling to you because of that. Went back to 100% cotton and will most likely stay there. Some companies are selling some really cool (not hot) shirts that are similar to a gortex type material. Looks just like a regular tshirt. I used one personally for a while, and WOW. It almost feels like your not wearing a shirt! Air just blows right through. Too bad they are like 40-50 bucks a pop round here
