I have come to agree with the popular stereotypes (Asian men are small, White men are bigger and Black men are biggest) for many and various reasons:
i) An India study in 2006 found that international condoms are too big for Indian men (Condoms 'too big' for Indian men)
ii) Chinese condoms are too small for South African men (Chinese condoms too small for South Africans: report)
iii) WHO and USAID have smaller width specifications for certain markets - primarily Asian ones (Chapter 5, Standards, Specifications and Tests).
iv) USAID found in the 1970s that US-sized condoms were too big for Thailand (Page on Enersol)
v) Good international penis size data from various countries reflect the stereotypes:
(Page on Enersol)
Taking the "country" column as a proxy for race, if we remove the Australian data (from 1995 and 1998 - even then Australia was a diverse nation, with 23% of the population being overseas-born and 27% of the native-born population having at least one overseas parent, making the data hard to interpret), we see that Nigerians have the longest penises, followed by US Africans, US Caucasians, Brazilians, Thais and then Koreans. Even if you remove the Nigerian sample for its small sample size, the US Africans still have the longest penises (looking purely at length). The circumference data has a similar ranking for the samples.
vi) Non-Asian men who go to Japan report that you should bring your own condoms, since Japanese condoms are too small.
vii) Another Asian friend tells me Durex condoms are too small for him and always slip off. Japanese condoms provide a better fit.
viii) Someone I know who's slept with many men of different races says the stereotypes are true, and dick size is correlated to body size (since Asian men are slight, white men are bigger and black men the biggest you can see how the stereotypes apply).
ix) A black male friend says Asian girls are always wary when they see his penis, and he has to be gentle with them.
x) A girl I know who's slept with a lot of men of various races says non-Asian men are bigger.
xi) A girl I know who's slept with quite a few White and Asian men say the White men are bigger and that they say Asian girls are tighter.
We should not ignore reality just because it is politically incorrect: the implications to sexual and reproductive health of pretending men of all races have the same penis size are disastrous.