Hmm, I wonder if it's better to spend the money and keep a Mac Pro long term or buy iMac's more frequently?? Right now, the iMac 4850 is right for me, but I hear because it uses mobile parts it's more prone to break down and it's difficult to fix and upgrade. I could spend the money and get a Mac Pro and keep for the long term, but technology changes so fast maybe I am better off buying iMac more frequently (every 2-3 years) versus getting a new Mac Pro every 4-5 years. I think price-wise I would save more money buying the Mac Pro every 4-5 years versus getting a new iMac every 2-3 years. What's your opinion? Thanks!!