I do remember watching some documentary about penis size a few years ago and the alleged average 6 inches was called into question with the implication being when asked directly most guys added on an inch or so to save embarrassment.
I have to say when changing in the gym it's "all guys together" and without looking you can't help but notice most guys aren't much to talk about which makes me feel a whole lot better about myself, the guys who clearly take roids always make me laugh as they seem a bit shy about getting showered
Think there are cultural differences with black guys tending to have slightly larger cocks and asians being slightly smaller.
I always used to sweat the fact i wasn't huge when i was younger which wasn't helped by the fact some close mates were well reported to be 8 inches and took the piss accordingly which majorly fucked my self esteem etc with girls as a teenager and into my 20's.
Still wish I was larger however like others have said providing it works and I can punt a fit girl 20-25 years younger than me then
while my mates are getting next to no action with a fat munter, I love karma