1. This has been my dream car since pretty much my forever.
2. As others have said, balance between performance and practicality.
3. I plan to keep my car for at least 6-10 years. Aesthetically, I think M3s age incredibly well and don't look outdated like standard 3ers. It might just be that I am sentimental about this car, but whenever I see a well kept e46 M3 or on occasion an e36 M3 while out and about, I always say to myself "what a beautiful car".
4. Also on the aesthetic front, the whole "lion in a sheep's clothing" thing appeals to me. To most on the road, this car is probably taken as just another BMW 3 series. However to those of us in the loop, we know all about the beast that lies within. RAWR!
5. I know that I will smile every single time I get in my car.