I'm generally with Nygeel and Morgan here - I tend to approach a bunch of things from an almost Vulcanesque logic standpoint, and this is one of them. If my partner has Tab A and I have Slot B, which are meant to go together pretty damn well, why not use that? Seems like the most rational approach.
But on the other hand, I've been thinking lately about my being a wee bit more gay-leaning than I've wanted to admit before, and I've wondered whether at some point down the road, if I were to "bottom" for someone I loved (even though I'm much more of a "top" personality), it might become important for me to learn to do it "the gay way" vs. "the way that makes a truckload of sense from a pain perspective as well as a logistical one." So, there's logic, and there's "the mysterious calculus of the heart..." :-/ I admit that I am still sorting many of these things out myself, so all I can really do is wish you luck and encourage what others have - talk, talk, TALK some more together and make sure that whatever you do and however you do it, it's done safely and rooted in mutual love and consideration.