My head is spinning after 10 hours researching a new Mac purchase, and I could use some advice. I'm going to get a Mac Pro, even though I don't need a tenth of its processing power at the moment. Reason is, I keep my Macs for a long, long time - can't afford to buy them often - so they have to be very upgradeable to stay useful over the years. (11 years in the case of the Mac I'm typing this on!) My options are as follows (the prices may seem steep to anyone in the US, but I'm in Europe, and we always have to add around 25%): ====== 2006 Original Intel Mac Pro, 2 x 2.66 GHz -- This is a used machine, upgraded to 3GB RAM and 3 hard drives totalling 1.7 terrabytes. I'm thinking of offering $2,300 for it. Reasonable? Jan 2008 Mac Pro, 2 x 2.8 GHz -- New, standard configuration, at $3,300. 2009 Nehalem Mac Pro, 1 x 2.66 GHz -- New, standard configuration, at $3,100. 2009 Nehalem Mac Pro, 2 x 2.26 GHz -- New, standard configuration, at $4,100. ====== The dual Nehalem is probably way over the top, but I keep oscillating around the other three and can't decide. If I bought the Nehalem single-processor machine, would I be limited to single-processor CPU upgrades, if one day such things become available? If not, the Nehalem 1 x 2.66 GHz looks better than the slightly pricier, year-older 2008 2 x 2.8 GHz. Considering I'm looking for longevity here, would it be a mistake to buy the 2006 Pro, since it's already 2.5 years old? If not, I could save $1,000 and get a dual-processor Mac with massive storage. Your thoughts would be much appreciated. TIA, Chris Adams.