the "dead" system is actually vitally alive. There are still a lot of Contax' around. Phase/Leaf wouldn't provide Contax mount if it wouldn't be profitable (they sure don't do it just because they like Contax so much - though they like Contax very much ).Most here have Mamyia or Hassey and it is understandable that they are not going to comment favorably on a 'dead' system.
I think it's understandable for a working pro who needs 24/7 service to rule out the Contax system today. Though it is really inexpensive to avoid any service at all by just buying one or two back up bodies and a second copy of the most important lenses. I sometimes look at ebay for lenses. A few weeks ago by accident I got a 2.0/80 for €210,-. I don't think someone has ever used it... it's like new.
Service is still provided and even if not you'll find the guys who can service the camera and lenses. At least here in Germany it's quite easy to find them.