Mrs. EastInWest prefers it inside and will never ask for it outside, although she doesn't mind a bit. She consistently orgasms when a man orgasms screwing her, and the more she screws, the more she wants to. It's kind of a spiral where once you start, it's going to be increasingly disappointing for her if you don't finish inside her.
I enjoy both depending on my mood, but really do love seeing a messy facial/breast shot, whether I'm delivering it or not. The first scenario we ever discussed as a possible swinging-type situation would be her sucking a couple of men off and letting them finish on her face and chest while I kick back with a nice glass of whiskey. That was just dirty bedroom talk but it took a couple of days for her to ask me, in the car, if I would really like it, because she thought she'd been thinking about it and could actually probably get into it.