Perhaps I've just been unlucky

I have 10 Kodak CD-RW's, three years old, I use them in strict rotation and each week one of them is erased and re-used as an audio CD for the odd times that I use my wife's car. Additionally, they're used for Mp3 CD's in my Rio MP3 CD portable, but that use stopped with the arrival of the Karma.
They show no sign of letting me down so far.
CD - R's that, at one time, I used for back - up are temperamental: for instance they'll work in one drive and not another with no apparent reason.