What you're asking has been asked many times over and.
However, I'm not into "hung" really, nor am I a size queen due to the fact that anyone over 7" tends to use their dick as a battering ram, not a tool of pleasure in my experience. I am of the firm mindset that my cervix belongs in my vagina, not my throat.
As for the length vs girth debate, I prefer a bit more girth to give some stretch and fullness. 7" by 6" would be "ideal" to me in the build a dick factory.
I've had a couple larger than preferred dicks, and I've not been turned off by them exactly, but I wouldn't go back more. Not because they were too big, but didn't know how to use it.
If someone was too thick or too long though, yes, I think I'd have to hit the breaks. Simply because my body is not made to handle it, and sex would be not fun and potentially painful.