I'm curious to see how the new X5 looks in real person with the base 18'' Rims. I currently have an E70 X5 30d with the base 18'' rims and it does not look too bad; as the general proportions of the new X5 have not changed very much, it should not look too bad either....at least I hope.
Base 18''s will most likely be my choice, as I do actually use the car once a week in real off road conditions and some times there' s lots of mud involved...and 255/55 R18's size is available for A/T tires.
Here are a couple of pictures of the type of terrain I have to go through on a weekly basis (if it's dry is no big deal, things get interesting when it's raining....). When I took the pics I was with my wife's X3 35i, that is also surprisingly good going though that stuff
Alessandro