There's a lot of misinformation in that thread, and bias. Of course, there's always bias in car forums, no the point of excessiveness. You'll find it here to, but in favor of what you want.

Here's my story:
I never cared about cars until I first saw the Audi TT. Its gorgeous and unique styling won my heart. I didn't know anything about performance (for which it often got reamed by reviewers and biased internet forum dwellers). I had to have one, so I saved up my pennies and 18 months later had one. I lvoed it, loved it, loved it, and it turned heads like you wouldn't believe. And then I had kids. The TT had to go.

The TT was replaced with a Charger Daytona. Great family car, gobs of power, and it turned heads. But it was lacking in something - that feeling of integration that you get with the road when driving a small sports coupe or roadster. That feeling of being one with the car and the road, where power is not so important as road grip and handling in the curves.

I had loved the appearance of the Crossfire since I first saw pictures of the concept vehicle at the European auto show. I finally had an opportunity to rent one in '06, and I took it through the curves of El Dorado in CA. I thought it handled great, especially forgiving and easy to predict its behavior. I was very pleased by my rapid adaptation to the car. And...duh...it turned heads (you seeing a theme now?). I had to have one.

I finally obtained some extra cash this year and found myself able to acquire a Crossfire in additional to the Charger. I had originally planned on getting a used model with 50K+ miles on it, because I had set a price limit of $12. That plan was tossed when I saw how cheap Crossfires were going in the market. I ended up getting one with 21K miles for $14.5K.

So now that you know my story, here are my responses to your questions and points made in the thread.

1. It is not crappy American engineering. Everything under the skin is German.
2. You correct about reliability. Although I tend to despise Consumer Reports for perceived bias against American and German cars, they did rank the '05 and later Xfire as one of the more reliable used cars on the market in this year's auto issue. However, all your replacement parts are German, so indeed repairs could be expensive.
3. The market is great for Crossfire buyers right now, because it does seem no one wants one. I tend to agree with "The Vanishing Boy"; it's the American nameplate that does it. People tend to be very image concious and vain, and shy away from spending $35K on a car with a Chrysler badge on it when they could spend the same amount and have all their friends "ooh" and "ahhh" over a Mercedes, Audi, or BMW badge.
4. I don't think you'll be happy in a Z. I like the Z. I think its a great looking car, but it is one the big side for sport coupes. Having never driven an S2000 myself, and can't really speak for you, but the S2000 is small, like the miata, the Crossfire, and the Z4. I think you'd find that the same sensation of "car/road integration" may be lost in the Z.
5. I like the transmission. Solid snap shifts, but occasionally difficult to shift into 1st.
6. It is a unique car with genuinely different and characteristic styling. I know the miata gets high marks every year from Car&Driver for performance and value, but whenver I look at it, I yawn. Just looking at the Crossfire excites me.

Bottom line is, why are you asking? Why do you need convincing/persuading/disuading? It's your car, you are the one who has to drive it. Go rent one. Go for a test drive. If you like how it looks, handles, feels, and most importantly you like how it makes YOU feel, then get one. Who cares what a bunch of internet forum dwellers thinks?