... the answer is Sax!
I think the trick is that they wash the *inside* of your windows as well as the outside. Overall, I thought the service was fine. Nothing to write home about for the regular washes. I have never gotten the detailing. There was still a little bit of dirt on my floor after it was vacuumed, but considering that my driveway is essentially a modified sandpit -- see the Myers Real Estate review for more on that -- I was not surprised.
The price also seemed a little steep to me, but then I'm hardly an expert on the going rate for full-service car washes.