I've owned an M5 and it's a very nice car but they do start to look a little outdated for my taste. I don't like the new M5 so if I were to get an M series it would be an M6. Currently I have an Audi A8 and it's my favorite car in the world. It's comfortable, it's spacious, it looks great and it's loaded with gadgets that will keep any geek happy. However this is not a performance car nor is it intended to be one. The top speed of this car is 155MPH and it will reach that speed in no hurry. This car is for cruising in comfort. If you want something that looks great, has some bling value to is and is faster then a Viper or 911 look for the Benz CL65 AMG. Of course with a price tag of $179,000 it better be fast (
http://www.mbusa.com/brand/models/CL65.jsp). Realistically if I were to get rid of my A8 my next car would probably be a Benz CL500.