Nothing has broken yet, and the way I drive, that's saying a lot. This car really takes a beating.
I really love this car. It's reasonably quick, gets great gas mileage, and handles wonderfully.
I'm very impressed with the performance and comfort, but I really don't like that the after-market hasn't accepted this car yet. I have been unable to find much at all in the way of go-fast parts, or dress-up parts for this car. It's about the only thing about owning this car that disappoints me. Why should guys with Hondas and Acuras have all the fun? This car would respond really well to some basic tuning.
Regarding aftermarket support, you may wish to look in Google Groups, for alt.autos.daewoo, then look for an entry titled "List of 'alternate' Daewoo parts"
Good luck..
As far as tuning parts go you should check out team sharkracing. they specialize in aftermarket parts for korean cars.
Check out daewootech.com.