I don't put on singlets. I see putting on singlets as old fashion and not what I should be doing. I want to feel free always and putting on singlets ruin that for me.
It depends on the material of the singlet. If it's not pure cotton, I will never put it on. This is because pure cotton feels cool on the body when it's inside unlike any other materials.
I don't see anything wrong with putting on a singlets as a guy. It makes you look stunning and cool each time that you dress. It is something every man out there should see as normal as long as the weather permits that.