interesting comments on forged vrs. cast etc. but let's add a dose of reality... BMW "turbine" forged wheels (which you probably have on your 850 - i do) are great but they look like something chevy designed in the 80's. Keep 'em (doubt they have much resale value) and put your ZR tires on them and use them for track days and that trip to wyoming. buy GOOD replicas, keep your speed below 130 ( i rarely get over 100 and i'm pretty nuts ) and make sure your tires are in great shape.... tire failure is the big threat at high speed after brain fade... my .02 - John