The 5.0i is awesome, but the the 3.5i is as good as the 4.8i was a year ago, so basically you can have what was the best X5 6 months ago in the 3.5i now, it is still fast and fun to drive, much better than the old 3.0 was on power, but if you are addicted to power, the 5.0i is the way to go!