Can't believe you guys (Americans) are so eager to change beautiful and sexy stock wheels for these vulgar wheels with bolts/screws around them (what those gangsta things are called) from HRE, ADV, BBS. American wheels were a fad, I had seen some of them 7-8 years ago and they lost popularity in only a few years, as did the neon lit wheels and circling gangsta wheels
All M5s that I've seen in Europe have stock wheels and keep stock wheels forever, they're considered to be harmonic and part of the car's design package which BMW's world class automotive designers work for years on. With respect to individual choice and tastes, I will never understand you and it pains me every time someone shows off his car with vulgar wheels. If you're not sure of how good your taste will look objectively, it's wise to let it be stock.