I have spent a fair bit of time thinking about this over the past half a year or so. I also ran across an article on another site that put things into perspective for me. It was written by a sub who acted out her pain through BDSM scenes but felt horrible afterwards. It stopped her from cutting but she acted out her pain through BDSM. She was not doing it for the endorphin rush. She felt horrible after these scenes. That is not so good. That to me, is her playing her abuse out over and over again.
For myself I find that the fact that I can feel power over me as being a 'safe' thing adds the balance that I need to offset what has happened in my past. For most of my life I saw power over me as a very bad thing. Realizing that power can be rewarding as well as add value to your life AND that people can use power as a genuine gift of love is a difficult thing to settle into when you have had an abusive past, but once you trust it - there seems to be no turning back IMHO.