If i am going to be 100% honest, my scar was a one in a million, the internals were wank! But i think thats down to the fact that my one was a "shop model" and was being stored in crap conditions! My friends on the other hand is still shooting as if it was brand new, two years later!
Yeah I've seen no bad reviews on it. If it did happen to fail it'd be shear bad luck on getting a defective one. Best look on well known websites. ZeroOne are out of stock on them but they're getting restocks in soon so maybe try checking them out?
If you look hard enough you'll find negative reviews on ANY gun. The US guys seem to favour the VFC ones so they'll mercilessly slag the G&G models mostly because they have higher FPS limits which introduce different issues with the hardware. As I say, mines been faultless.