I did this and it did go wrong. I waited 3 months and stupidly thought that would be long enough and that I could handle things being no-strings, etc.
And I won't lie, the sex was fantastic and it did give me a good boost to feeling like maybe I wasn't broken, sexually. But then I kept reading into things, thinking ooh we have a great connection, etc, maybe he will end up falling for me, maybe this could work out. He was far away as well so I was sure I wouldn't get too involved, still did though.
Anyway then he spelled it out really clearly that he didn't want a relationship and we agreed just to be friends and not to sleep together any more, and I was really really gutted, it was really strong, like I'd just been dumped by someone I'd been seeing for a year or something. I hadn't realised how emotionally fragile I was at the time to be hit so hard by it. And then we did end up seeing each other and sleeping together but this time the connection bit was sort of gone and it was just weird and I ended up feeling really used and disconnected and I got quite hurt by it, and so I did the coward's thing and just stopped contacting him, and deleted him on facebook a while later when it became clear to me that he had never intended to be friends.
But.. having said that, I did approach the relationship with a sense of caution and a really strong sense of "What would MN say?" (
) and I did learn quite a lot about boundaries, even if some got pushed, I got a sense of what a non-abusive man is like in various situations, I learned that being dumped hurts but isn't the end of the world, (someone said here at the time that it was a "clean hurt" unlike the kind of hurt I felt with XP when he used to play games etc) and I could see clearly the difference between having relationship drama in my life and just being single, not having to worry about anything like that, so it was a useful distraction for a while (didn't get DS involved at all) and helped me come to a place where I was happier being single than looking for that new relationship thrill, and I think that was very valuable.
I think you're going to do it anyway, (I would ), so my advice is just keep some distance, don't get DC involved, if you start feeling like you're sitting around waiting for him to call etc, make yourself busy doing other things, in fact do other things anyway. Don't let all your happiness depend on him, consciously make an effort to seek out other things which make you feel happy and/or fulfilled as well. Go at a slower pace than you think necessary, to counteract the fact your judgement is likely to be off. Repeat the mantra, what would MN say? 
Imagine posting for advice, if you KNOW everyone would say run, consider running!
sorry for the essay!