I've been picking up used books from both series' for the last month or so. I plan on starting one of the series in the next few weeks, as soon as i finish reading the book i've already started and Cutting for Stone. I know in other threads some posters have indicated that they've read one or the other series, or both, but i wanted to get a thread started to get everyone's opinion on these books. If you have read them (either one or both), how do you like them? Are most of the books in the series good or is there a lot of variation in quality among them? Do i NEED to read them in order? If you have read both, which one do you prefer? Thanks!