Okay, so I have some squicks about 24/7 "lifestyle" BDSM. And this book is not about that, but skirts close enough to trigger me, particularly because the hero is the heroine's boss and also she has some serious insecurity issues (though she's well aware of her own professional competence).
But this book explores the complicated psychological and logistical issues involved in a kinky relationship. I especially liked how both h/h want to make sure that they can build a relationship between people not just interlocking kinks and conflicted about the degree to which they are their proclivities and how to make peace with that while also trying to be more than just their kinks to one another.
Well-written with good characterization, which is only proved by my twinges of discomfort. Also, Dryden does a good job depicting the almost-indescribable feelings-emotions-urges evoked in BDSM participants, and possibly a better job making her intelligent characters fumble with language in their attempts to articulate the aforementioned.