I've never had an Apple-manufactured cord stop working - I still have the FireWire 30-pin cable the original iPods used. I stopped buying the cheap knockoffs years ago, except for last fall when I forgot my iPad cable on a business trip and had to buy a no-namer at a train station. It worked for three days and then shorted out. I took the connector apart when I got home and the internal components were trashed. YMMV.
Also: don't yank on your cords, regardless of what kind you use. Disconnect them by grasping the connector and pulling steadily. Not saying you, OP, do this - but it does lead to the early death of lots of charging cords.