My experience with their support has been 50/50, to be honest, but they did replace the motherboard on my 2011 15" MBP thanks to that extended video support program. The main issue was the failing graphics card, but my headphone jack and SD card reader weren't working either (common issues with my model) so now everything's 100%. Basically got brand new internals.
Their products are expensive, so a lot of people feel like everyone should get a perfect product, and while I agree that this would be ideal, it isn't very realistic when we're talking about mass-produced devices in a process with some error margin. The best Apple can do in their position is offer full refunds or exchange the defective unit for a working one, and I think they handle that pretty well most of the time.
