Well, from my experience (which is limited) there is a slight correlation between penis size and race just as with any other attribute. Take height for example. Sure there are people of all sizes in every race but it is no secret that certain races are generally taller than other races. For example, people of African decent are generally taller than people of Asian decent. Of course there are exceptions like Yao Ming, but honestly, how many Yao Mings are there in the world? Just in example, i am NOT being being racist (intentionally).
Anyway, I think instead of pretending that the differences are not there we should embrace them. After all, it is our differences that make us similar. I know it sounds awkward, cheeky, and cliche but it is true. We are so different that we are alike because you can be 100% certain that no two people will be 100% identical therefore making uniqueness a common trait

(think about it)
Anyway back to the topic at hand. I've had one experience with my arab best friend who claims to be 100% straight, needless to say we fooled around a bit. I was very shocked to find that he was roughly the same size as me. Granted I was a little longer but he was a little thicker. He doesn't carry himself like someone with a nice member, he's kind of shy and insecure but that is probably due to him being foreign and a virgin (which somehow is a big deal). Well anyway he was verrrry good for a virgin and his cock was nice, nothing astonishly huge, a little above average. I assume a good percetage of Arab men have nice cocks. Not to mention they are (from what I hear) great in bed and oh so fucking HOT.