I would have it examined. It's my belief that every used m3 has been toyed with or revved to no tomorrow by the previous owner(s). Unless you personally know the previous owner, I'd just assume the above for the car. Now, it doesn't mean it's a bad buy, but I'd just look more closely for signs of wear and tear than with a regular e36 because maintenance costs will be a little higher.
Also, check with your insurance company to make sure you can afford the insurance. The worst feeling ever is buying a car and then finding out you have to pay $400 a month or more on insurance
If you get the car though, I get dibs on riding shotgun at one of the up and coming meets