This shirt runs just slightly small in my opinion. I am average build, 53yo and definitely NOT muscular. The material is just a bit above average weight, but has thinned out slightly after about 10 washings; should wear well (meaning last a long time) if well cared for.
The logo silk screen is not "splattered on" and you will not notice it during wear - you know how some silk screen shirts are (heavy and uncomfortable in humidity. This shirt is not uncomfortable in warm, even hot, weather. Note: I ride year round in Phoenix, so unless you're in more than 110 degrees summers this shirt should be no worse than any other.