If I was allowed, I'd say it would depend upon my partner. Certain partners I think I would have gone with sub as I tend to find it slightly more fun, but others I would have said dom. If I had to hedge my bets for a permanent role though, I would choose dom, because I believe (perhaps mistakenly) it is easier to find a girl willing to submit to me that it is to find a girl who would agree to domme me, and know what to do.