its not user error..they leave temporary files and 'trash' folders on every device you connect them too...its annoying. I am fortunate enough to own a Powerbook that I need for a couple of specialists programs, its nice computer, but I have always preferred ThinkPad T Series as my everyday machines due to the feel of the keyboard and better software support from a stable windows environment. But I do get the attraction to apple equipment and its nice to have a choice.