I had a relatively heated discussion with my OB, as he wanted to induce at 41+3. I tould him in no uncertain terms that it wasn't going to happen. I would go in and have scans of the baby every day, but if he was fine then i was going home.
My mum went to 44 with me and 42 with my sister. My nan went to 46 (ouch!) with my mum. So i figured there has just got to be some genetics involved.
Finally, i went naturally at 40+6 in the end my son was only 6lb15oz (3.1kg) and the OB conceeded that he could have cooked for longer if need be.

I say if you comfortable nad the baby is being scaned then it is your labour and birth. Ultimately all we really want is a healthy baby.