I saw there like dozen of topics discussing different penis sizes and I was thinking of the all the possibilities which lead me to conclusion:
If men would have the option to choose just different penis size, every one of them would choose the biggest possible, there would be only few exceptions, maybe less than 1 %.
The only possible option to choose would be:
1. Regular size like every one is having now
2. Thicker one but a little bit shorter
3. Longer one but a little bit thinner
That way no one would win, all would have their advantages with limitations and men would finally have option to customize their most important thing.