One Last question - In case of GPU Gems there are 3 versions of the book and in case of GPU Pro series there are 5 versions of the book and the 6th one is coming year,my question is which one should I read like I mean should I go for GPU Gems 3 or GPU Pro 5 or should I read all versions of GPU Gems(1 to 3) or GPU Pro series(1 to 5). 