These are $5 for a reason.
http://www.reddit.com/r/haskell/comments/1rj2jq/book_haskell...
http://www.reddit.com/r/haskell/comments/1rj2jq/book_haskell...
It really seemed their plan was "James takes almost all the risk and does almost all of the work but James does not get almost all the money."
I dont have enough packt titles to evaluate their general quality, but at least I found their early solr books useful(it was also the only book on solr back then, so not much choice :)