While getting my E53 serviced had the oppurtunity to compare the X5 and X6 at the dealer ... my 2 cents - the X6 is definitely growing on me as far as looks go - even more so in person (rather than pics). There is definitely some 'utility' in the X6 - you just cannot load tall objects - i don't think my golden retreiver can climb up and enjoy a ride standing up. The X6 does look and feel sportier than the X5 (35 vs 4.8). The biggest downside to the X6 is getting into and out of the back seat - i not only knocked my head (i'm only 5'11), i had to twist myself out (much like the Infinity FX45 - which in my opinion is the only direct competition to the X6). To sum, if the technology in the X6 is transferred to the X5, the choice would be even simpler - X5 all the way!