I have never been challenged to show it, but then again I don't have a monster size cock, just more than average. as I grew up and dated and fucked various women, it got around I was bigger than average. I have always been a grower not a shower. on 2 different occasions when I was younger, I had a woman, actually put her hand in my pants and grab my cock while I ws in crowded bar(s), eventually leading to me fucking them later in the evening and at different future times.
when I was dating my now wife, she said the girl talk(rumor) was that I was nicely hung. she told me this after we were married. she was a sometime friend of my ex gf, who told people I was hung like a horse. she got this impression because she had only been with one guy, and she had a small pussy. my now wife also said, that some girls thought I was handsome, ugly, too skinny( and therefore to skinny to be hung), too tall, and superficial, did not like relationships, and pretty much moved on after getting what I wanted(true). my wife also said that she was quizzed by the same group of girls after we had had sex numerous times, and she told them I had a nice fat cock which wasn't supposed to be on a skinny guy, that I had given her her 1st orgasm & many more since, and that was great in and out of bed. one time, she was asked how big i was about 1/2 an hour after fucking. she just giggled, and spread her hands about a foot apart. OMG!! was uttered by a few friends. after we were married, my wife was specifically asked for my dimensions which at that point she had never measured me. she got a little protective of her man and a little wiser about any details. her answer became "my husband is a large, well built, fully developed man with a toned body, and I love all his features and overall he is very good to me physically and mentally. I love him dearly. you draw your own conclusions." I have actually heard this on 3 occasions. after the first time I asked her later what was that about, she said Debbie wanted to know how big my cock is. then after that, when I heard her little statement, i knew what was going on without actually hearing the question being asked. my wife has also been asked if she has ever cheated on me, or had the desire to find a "bigger" man. her answer to that was she doubt if she could, and really had not interest or need to do so. that tells the ladies that my lady is getting the right stuff at home.