Here's my take...
I am also of the hellafunctional crowd and agree with Evan in that I prefer to squeeze as much rubber on a wheel as I can without "ballooning" the tire; function over form if you will. I have 18x8 and 18x8.5 factory wheels on my Z (the P5 currently don's a sweet set of jackstands) and run a 245/40 on each wheel and that is the look I'm after. I can tolerate a little stretch, but not so that you can tuck wheels that fit within a visa card's width of your fender. The recommended wheel width for a 205/40/17 is between 7-8", why not run that? 205/40 would still look plenty stretched on a 8" wheel but on 9 it looks retarded. When you can start to see the inner lip of the wheel rim, it's time to go wider on the rubber. Not to mention the safety concern with stretched rubber, or the reduced life of the tire and the extremely reduced contact patch in some of the more extreme-camber examples.
Again, we don't pay your bills or consumables for your car, but I say that your car (as it sits with the MSP wheels) is one of the cleanest examples I've seen. I'd cry a little to see you rolling/pulling fenders and tossing camber at it to join this lifestyle fad. To each their own though, that's what makes the car culture so great.
Rediculous:
Still too much:
Still too low on the offest (thus more camber) but a clean stretch:
Here's a 275/40 on a 17x9, also on my Z, while there is no stretch, its very squared and all business, my preferred look. This was my track setup, I run the 18's for DD duties and it looks a bit more pleasing aesthetically than the 17's. For reference, you're talking about taking 70mm of tread out of there.
And for laughs, nomNomNOM:
? Point taken. 
