2 1/2-3 really. 1st to the good:
It was a nice change to see the woman propose to her man in the beginning, that she knows (or in this case thinks) that it will only be because of her very large dowery. It was also nice to see Devil confess out loud his love for his Duchess Honoria (which he never has done in the years since Devil's Bride). The little Ashfords were cute and I glad at least one family member isn't being kept on the shelf until her 20s.
The things that Bugged:
Amelia, whilst thankfully less 21st C type wild than twin Amanda come of as something of a cypher in her own book, you almost get more of her personality in the previous book. She's perfect at everything, everyone adores her, she knows immediately how to run a large country estate, her mother in law adores her and her younger sisters in law immediately go to her over their own mother for everything. Now this would be all very well if the rest of the plot were more than 10 page sex scenes interspersed with 2 pages of dialogue planning the next sex.
The main angle is 2 people madly in love who for a not exactly convincing (IMO) can't tell each other for 400 pages because of the "power" each would gain over the other. They are convinced each married the other only for convience and money, which is fine except for the passionate sex 5 times a day.
Laurens regular mystery plot is weaker than usual, the plot itself never became interesting to me (petty theft from various aristocrats homes) and the villain was even more transparent then usual and is case closed in a couple of pages at the end. And the whole sub plot about it being for Edward (the previous villain) doesn't really get resolved too well.
The book is also too long by at least 100 pages and feels drawn out for the sake of it. I love a good sex scene as much as the next reader but tehy happen so often and are so techincal that they become boring and redundant, especially with a thin plot to begin with. I enjoy Laurens writing style but it does start to become *too* wordy.