2006 BMW 325XI Tires Problems

THE VEHICLE WAS USED UNDER NORMAL DRIVING CONDITIONS. THE TREAD OF THE TIRE BEGAN DE-LAMINATING FROM THE TIRE AFTER 40K MILES. FORTUNATELY THE CAR WAS IN FOR SERVICE AND THE MECHANIC FOUND THE DEFECTIVE TIRES BEFORE THEY CAME APART WHILE DRIVING. ALL 4 TIRES WERE REPLACED, BUT THE OLD TIRES REMAIN IN MY POSSESSION. *TR

I HAVE HAD THREE SEPARATE INSTANCES IN A NINE MONTH PERIOD STARTING IN MAY OF 2010 OF ALLOY WHEELS CRACKING ON MY 2006 BMW 325XIT, WHICH HAS RUN FLAT TIRES. THE DEALER SAID IT IS FROM HITTING POT HOLES, CURBS, OR PARKING BLOCKS. I FIND THIS TO BE VERY UNUSUAL AS I LIVE IN A WARMER STATE WHERE THERE ARE VERY FEW POT HOLES, AND I HAVE NOT HIT A CURB OR PARKING BLOCK. MOREOVER, IN THIRTY-THREE YEARS OF DRIVING, I HAVE NEVER HAD A SINGLE WHEEL CRACK ON ANY CAR THAT I OWNED. I ALSO OWN A 2002 BMW (THAT DOES NOT HAVE RUN FLATS) AND HAVE NEVER HAD A WHEEL CRACK ON IT. A REVIEW OF THE INTERNET REVEALS COMPLAINTS BY BMW OWNERS WITH RUN FLAT TIRES EXPERIENCING REPEATED WHEEL CRACKS. IT APPEARS THAT THE RUN FLAT TIRES MAY NOT COMPATIBLE WITH THE WHEELS. YET, NOTHING HAS BEEN...