I do Photoshop work semi-intensively and would like to do a bit of video editing in the future. I decided to buy a Mac Pro because of their expandibility and knowledge that (hopefully)it will last me a good 3 years. However, I'm trying to save every dime and the 2.0 GHz Mac Pro looks to be a good deal. However, would it be better to save for the 2.66 GHz version? Would it make that much of a difference?