Which would you choose?

[tony]

I'm enjoying my current car but I'm wanting to step up as a graduation present to myself, the 3 I'm considering;

Audi S5
E92 M3
Porsche C2S (06-07)

Its still months (possibly a year) away, if I was irresponsible I'd go get one now but I care not to be car broke like I was previously. Speed doesn't matter to me any more, you'll never see me drag race anyone ever again. What I'm looking for is driving experience, something that keeps a smile on my face. The S5 looks appeals to me but its underpowered compared to the other two. The C2S I lean toward and absolutely believe would be the most fun but I want something relatively comfortable for my fiance and I on road trips. (which I think the porsche is still capable of) The M3 is the mix of the 2 but when I compare it to the C2S I just can't justify getting one. I'll probably end up with the C2S but I wanted to see some other opinions. Which would you choose?