Leo says there's not much difference between the two. He uses a Mac Pro at home and likes it, but it's not very upgradeable, and any upgrades he could do would have to be external. On a PC, if he gets a tower case, upgrades are easy. Leo just got all of the video editors at TWiT Dell PCs and they will be moving to Adobe Premiere. The Mac Pro is expensive for what you get, and for pro video editors it's probably not the best solution.