I had a German buddy who was about 8.5 and uncut with a nice downward curve. I could get on my knees and actually take it all down my throat. He would take his time prepping my ass and then could fuck me for almost an hour.
But the bigggest I ever had was an Iranian medical student in the DC area. It was a hookup, so I didn't measure it. But based on my German friend, I would guess 10 or maybe 11" and pretty thick. We first tried using regular condoms and he busted three just trying to put the thing on. For the second night, I bought some magnums. I couldn't really get the whole thing in, so he fucked me with only about half of it
BTW, I asked him about is background. He told me his school principal back in Iran had first turned him.....pretty dangerous considering this was after the revolution.