You have to remember that mac pros are not upgradeable,however they are expandable.You can add more ram than any human can afford,you can run a truck load of displays and put in thousands of dollars worth of graphics cards.But you can do all that the day you buy it if you can afford it.However you will never be able to upgrade it,such as adding newer graphic card and such.I bought a Mac pro not even a year ago and it has a graphics card from a different era(geforce 7300 GT)and I can`t get anything I consider an upgrade.This will be meet with mac freaks bashing this post but this is how it is.Get the imac unless you need to expand because macs do not upgrade.