I have 8 inches and I'll be perfectly honest with you it depends on the vagina. I've recently spit up with a girl who had a really short vagina and I could only get a halfway in doggy style maybe three-quarter away and she always complained and I could always feel my dick rubbing on her cervix and she didn't like it.

Are the women I've been able to pound with full frost and they've enjoyed it to be honest with you? I struggle with really tight vaginas.