To answer the question that started the thread, I don't know.
My first reaction was that I would go with the person who was compatible with me in all ways except BDSM.
But I know that in every vanilla relationship I've had, the lack of D/s in my life was always painfully lacking and I found myself searching for it.
Like TomOfSweden and maybe others, I cannot and never once have had an orgasm without a D/s fantasy or scene. Never. Although I feel that D/s is an intrinsic part of my being, I don't know how lucky I'll be to find a good mate, let alone one who is a true Dominant.
Most likely the best answer would probably be like cariad's- that if I can't have both, I'm better off with neither. Settling in any way just doesn't work out.
To address the issue of having friends and acquaintances outside of the Lifestyle- I have and enjoy both. And most of my vanilla friends do know about who I am and have no problem with it- and if they did, if they wanted to judge me, I'd have to say "see ya!"
But, I don't think it's closed-minded to not have friends outside of that circle- all people have a preferred choice of friends- whether it's those in the Lifestyle or those that are educated or those that have certain living standards, whatever... that's just someone's choice. Right? Right. I think most of us have expressed this already. I'm sorry. I'm being redundant. Well, heck, it's just an excuse to get spanked... oh, can you tell it's been too long for me? lol ;P