While diving on the Tiata in April of 1999, I encountered a very unusual problem with the German made teleconverter. It seems that the pins on this teleconverter are slightly shorter than the pins on the original Nikonos RS lenses. As such, the pins on the original lenses will eventually wear a very slight groove when mounting these lenses to the camera body which make the pins on the teleconverter not quite touch their contact points. This can be easily fixed but nevertheless it is disconcerting to lose one's electronics. This problem will not occur on all camera bodies and it is not really the fault of the teleconverter.
The new 18 mm rectilinear lens is awesome. It is sharp corner to corner at all apertures and provides true water contact optics for those willing to pay the substantial acquisition price. There are only a relatively small number of these lenses going to be produced so if you are inclined to purchase one, now is the time.
As of May, 1999, there seems to be no delay in getting parts for repairs of this camera despite Nikon's discontinuance of production two years ago. However, purchase of this body in used condition now demands paying a premium over the original new camera acquisition costs.