Marshall

After successfully "training" my wife's butt to acccomodate me anally, I would say that I have the ability to move as deep and be as flexible during penetration as vaginal sex. It has taken sometime and a very patient technique to get there though. If too much lube is used, her anus can feel not quite as tight as her vagina. This is probably due to less friction with the lube vs the natural lube of the vagina.

I also had the insertion problem, until recently. We tried doggie and her on her back with very little results. However, with her on top, made all the difference. She just reached around and kept easing it in while firmly holding the base. In no time, I was in and she was riding away!