I own both the Z800 and the Z600TC (along with the 500PF, the 180-400TC and the 180-600 [...] ).
The beauty of the Z600 and the only real reason for me to leave the 800PF behind is its versatility, nothing beats being in the bush and be able to reframe back from 800 (840) to 600, while gaining a stop+ against the 800.
However, when not on a fully (or mainly) birding scenario, the 180-400 TC + the 800PF is "
the" combo for me. The 184 for "everything" and when needed more FL, the Z800 is the champion (in this context and considering weight as well).
I mean, you can travel
very heavy having the 184 and the 600 or, you can travel "
light" by leaving the Z600 and adding the Z800.
Now, if travelling really light, and only one lens is on the table, the Z600 AND a 70-200/2.8 on another Z8/Z9 (to take advantage of the 47mpx) would be my choice.
It seems a huge gap uncovered but if we need a wider angle, 200mm should do the trick, specially if cropping a bit. And eventually, having a 1.4TC at hand if all goes wrong with the shorter FL choice...
Either way, it's a luxury to have so many choices, specially with the high Mpx of the newer cameras.
Krgds, Marcelo
ps: thanks
@Steve for the video!