When I saw the title of this post, I honestly thought it was going to be about how 6 inch girth seems too big and how there are many girls out there with small vaginas who are uncomfortable even with less than 5" girth... some even slightly less than 4.5". Then again there are also girls who can take 6" and feel no pain at all, and even take more before feeling pain. You gotta think about the size of the girl... you don't want to rip them or have them feel pain right? We're doing this so they feel more pleasure, not for some masochistic female pain device, right? At least that's how it is for me. Besides at 6" girth you'll find it harder to get proper oral. I don't even want to think of how bad it would be to have coke can girth or 9". If it were physically possible it would be horrible, no one would let you use it with them so you'd be left with your hands. =|