Is the 3.0GHz Processor choice on the Mac Pro really worth the extra £££ ? Do you see the 3.0 totally flooring the 2.66 in any task in the future ? Im not sure wether to take a 2.66 with the MP, or a 3.0. I do want a future proof machine (Last aound 4-5 years), but I dont want something that will just be a waste of hundreds of pounds. Help !