Honestly, I couldn't care less about what driving a car makes me look like, but anyway, here's my take...
The Oscar Meyer Wienermobile would be so silly and ridiculous that I'd rather walk, but between the serious alternatives I think the Porsche would make me look like less of a berk, after all it's a lot more understated and has a nice classic touch.
The Ferrari (and this applies to the rest of the current Ferraris too) screams "Hey, look at me I drive a FERRARI, I'm rich, you're not". I'm one of those who think Ferrari lost the plot when the 360 was introduced. Also looking at it, I think the Ferrari lacks the clear identity the 911 has. If I ignored the badge I wouldn't be able to tell that the F430 is a Ferrari, whereas the 997 has perhaps the strongest design identity of all volume cars currently in production.