don't buy a 320 they weigh way too much, we had 99 430 and we should've waited a year to get the 55. Furthermore the 320 will not get that much more MPG, we currently have a '06 500 ml and I've driven an '08 550, definitely go (if you can) for one of those or the 320 cdi. BTW the 550 is nuts and out runs the speedo to about 60 mph and will spin up all 4 tires in 1st gear, I really want to drive a 63

__________________
2006 BMW X5 4.8is Lemans Blue/Beige/Dark Maple
-Nav, Comfort Seats, Heated Steering Wheel,
Rear Airbags, AUX Input
2009 BMW M3 Space Grey/Black/Carbon
-all options