Also, if you joined twitter and signed up to follow her tweets you received a further discount on the drivers. I don't know if this is still in effect but worth checking out. I think they were $49 each as compared to the listed $59.
I ordered six to replace the ones in my silvers. It took quite some time for them to break in. I can say that when I first received them they had hardly any bass at all and then after around 24 hours they woke up and continue to get lower each day.