I love the high performance luxury cars like the IS-F, M3, C63, S4, and the CTS-V. Its great for those who want a bit more "sophistication" or gadgets than the Mustangs and other muscle cars can offer, but don't want to sacrifice performance. If you think about what you are getting, those cars are actually a pretty amazing deal - you get luxury and high performance in a $50-65k package. To get each of them in seperate cars, you'd need to spend at least $35k for the luxury and $45k for the performance (stock of course).
In a couple years I'll have to make the difficult decision between using my savings for a condo downpayment or using a good portion of it for a new C63...