With my 2.4Ghz C2D MBP, USB and disk performance under Windows 7 and XP was always much slower than native performance. In fact, I used to see the CPU pegged at 100% when I did >1GB transfers in XP. My question for those with i5/i7 MBPs is do you notice USB and disk performance improved? Is it any slower than native transfers? Does the CPU go to 100%?