Never used to wear one on the road before I had kids, but since I insist on them wearing theirs, it's hardly setting a good example if I only wear mine sometimes...
After several years, it now feels so normal that one day when I somehow set off without it, it felt very, very strange..
Apart from the tenuous "rotational injuries" and the ONE study that seemed to suggest a correlation (note: 1 limited study a causal relationship does not identify) between helmets and drivers passing closer, I struggle to see a reason to not wear a helmet, whereas I can see a pretty obvious potential drawback of not doing
but not as light and well ventilated as no helmet.
Not as light, sure, but aren't there manufacturers now claiming that they have designed the vents so well that you get more airflow to the scalp than on a naked head? I may have dreamed that?