I say R8, but I'm not a huge fan of silver. I'd stay away from a Ferrari that old, because I think that to spend 80k on a Ferrari is kind of a douchey move, from a brand-whore sense. Something along the lines of "I just bought a Ferrari, it's 10 years old and I saved a bunch of money by getting it used." I also say Audi because for the reliability aspect. Watch the first 40 seconds of this and you'll get what I'm saying.
Even if it's only a weekend car, you still want it to work when you want to go and use it. That why I say R8.