My experience is that if the girl is really horny and into it and you know what you are doing the girth is not an issue. I am 8,5 × 6 and have had anal sex on regular basis with approximately 20 girlfriends during the years, newer any problems. If you try to force it or if she doesn’t really want it in her ass, just forget it. Good thing is that anal is not that rare anymore.
HeavyH