The first two books are quite readable and enjoyable, but the third and fourth books, whilst having sufficient to keep you reading, had a blandness - a sameness that did not pique your interest in a similar manner to the first two in the series. That's why I was in two minds about this series, and how I would rate it. I would rate the commencing books as probably 41/2 stars. With the last two, I was constantly wondering if I should keep reading or move on. On an overall basis I could not rate beyond 3 stars.