That was funny, Steve!
There's a certain something to the Speedster, as I'm sure you'll find out when it works the way it's supposed to. The BMW, being well-made of modern materials, will have a great degree of appeal for quite a while. The Pontiac ... well, maybe not so much in a couple years.
I believe (and those smarter than me can set me straight) that GM will only have to support the G6 for a period of 15 years past the date of manufacture. Inasmuch as GM cars are fairly homogenized, you may be able to find what you need for a few years after that, but then you'll be paying a premium for parts to put into a car which might not rate.
It'd be different (for me, and if it were my car) if the Pontiac made you smile every time you go for a drive, but IMHO it's kind of a generic platform design with a little extra horsepower -- and it may not put that smile on your face too many more years before it starts to have annoying little problems.
I'm generalizing, but I haven't had a GM product I was proud of since my beater Olds 442, more than 25 years ago.