Hello I am choosing computers for our teen center and I was looking at the 17inch I Mac and the 2 GHZ G5 tower. What we will be using it for is to do video editing, graphic design, and what ever else we might want to. We can' t buy computers alot so which ever we buy will have to last for about 2 to 3 years. My questions is which one is a better buy for the long term? I am concerned about the upgradability issues with the I Mac. I don't want to choose something and than have trouble because we can't add this or that. Also the ram limited I am concerned about. Which do you think is a good one? And Why?