I've read a bunch of flex books, some being extremely erroneous and some just being replays of the manual/api.
The one I just picked up Flex Solutions is great. I don't know how it does for errors, but I love the "cookbook" style and it does cover very typical challenges we have to solve as flex developers. I was especially happy to see they don't just cover 1 solution to each challenge but go into detail about how you may solve the problem with different techniques depending on the requirement. I look forward working through the rest of the book.
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