I give it and take it in this position with my wife and neither of us have any trouble with it, however to do lots of foreplay including rimming, fingering, multiple fingering, dildo and/or vibe, dildo size increase, all prior to full in anal sex. By the time we get to missionary we have been at it for quite a while. I do know that if her dildo id curing up hitting the prostate more I am way more affected by the stimulation. For me it is good but I do not think I could handle it without all the prior play. My wife actually loves it when we are having vaginal sex, she's orgasmed several times and in the heat of the moment screams for me to fuck her ass, at which time she changes her leg and hip positions for my next push to pop into her anally. Never had a problem, in fact she orgasms so wildly I can barely keep up with her. I get the same way at this juncture.