it all depends upon you. if you want to help the people financially that gave you such a wonderful operating system and gave u a choice to ditch M$ which otherwise would have been "not-there"|"impossible" (since MAC is not counted) then you should buy the cd's. well if you can't help financially (either bcoz you don't have the money or you don't have a way to deliver the money to right people) then you can download. thats all the philosophy thats behind open-source. either way you are helping the open-source grow. thats all they want and will probably need and thats all they have to say about your question.period.