Hi altchrono,
yes the 3506 is a nicely designed and exceptional to wear due to it's size. My
fascination for the skinny ingenieur line started with a black dial 3506 and
still hasn't fallen away up until now. At the beginning of my collecting
career i was deterred by the movement which was not built on an IWC own
construction. But this has changed now due to its robustness and
maintainability. I think a full set would be really hard to find, but if you
go for the watch only, it is more easy to find one in decent condition. If you
are willing to give it a full service in Schaffhausen, you will be impressed
by the outcoming result. I made the experience several time, the service is
flawless. From what i know the skinny ingenieurs where a success in
Switzerland, Germany and Italy.
Good luck in hunting
Cromagnonman
This 3506 shown in th eimage has not yet gone to the Service

