This is not a Regency romance. Rather it is a Gothic novel. All the books in this series have florid, preposterous plots full of mysterious old houses with secret passages, peculiar wills, missing heirs, secret children and crazy women who are (typically not) locked up in attics. If you go in with that expectation they aren't too bad.

Pros: heroines that aren't conventially pretty and accomplished.
Cons: ridiculous plots and rather unconvincing romances (to me at any rate). Also a surprising amount of talk about sex.