I made it to 28 before hair loss reached critical mass, and people started making comments, so I cut it short, the first time was a bit traumatic seeing my hairstyle disappear, I wondered if my skull was going to be a strange shape. Now it feels more neat, and balding is no longer a big deal. I'm lucky as it happens that a lot of my friends in my 20's who had the most luck/ability getting girlfriends also happened to be bald, so I didn't lose too much confidence. It hits some guys really hard though I think.