I read a consumer review at Edmunds.com (http://www.edmunds.com/new/2007/bmw/..._consumer.html )posted by one owner that he puts regular fuel on his 07 X5. I called bmwusa customer service and I was told that the new 2007 X5 CAN/WILL run on a regular fuel but they highly recommend owners to use Premium. I asked if it (regular) will harm the engine and the answer I receive is NO however, the premium fuel will burn cleaner than regular.

I guess it is worth the try. What do you think?