I'm impressed, PDX. I have no idea how, even with the small bits of evidence, you are nailing the model numbers on these hubs. Almost every Mavic hub in the 500 to 550 series looks practically the same to me on paper.
I like the look of the wheelset as it has a sleek, sexy look to it with fantastic vintage (NOS!) parts. The only problem is, I don't have an extra machine to put them on, so I'm seriously considering selling them. We'll see though. Isn't it always a matter of time before another frame comes into our C&V lives? I'm certain it's the law of attraction.