LOL ! Some doubt ....... no doubt! ||
P.S. That price you quoted may be for the new hand holdable DO 1200 f5.6 version!
There might have been a zero too much...:t:
Anyway, just extrapolating price (by focal length) from the current 400/4 DO ($7.5k) brings you to $11k. With additional weight savings, I would not even be surprised if initial price would hit the $15k mark for a 600/4 @ 2-2.5kg.