If I hadn't gotten to like the two main characters in the short prequel, An Accidental Seduction, I probably wouldn't have finished this. Somehow both of them managed to continually rub me the wrong way - and the angst caused by the amnesia (not really a spoiler, the book starts with it) did not see...
3.5 b ut having to choose between 3 & 4 only, I'll round up.