Couldn't agree more. D3X is a superb camera. For nature and landscapes, low ISO settings in conjunction with a tripod is the usual approach anyway. I'll use mine until it gives up the ghost.
Admittedly, the D3X is weak on higher ISO numbers, just like the D2X in its time. Didn't prevent them being excellent units and the no-nonsense immaculate handling is a big plus in the final reckoning.
I will keep on shooting my D3X till it dies. I think it was Lloyd Chambers back in the day (IIRC) that ran some tests with his D3 vs D3X and came to the conclusion that D3X is a
better 12 Mpix camera than D3. I didn't believe him, I thought it was just the honeymoon effect talking when he had just got a new D3X.
But I pretty soon changed my mind and currently I completely agree with him. Even at high ISO settings applying judiciously some noise reduction and then resampling the D3X image to 12 Mpix, it has less noise and more detail than D3. Even so, that shooting at "ISO 12,800" is possible with D3X. I do it with ISO 1600 and 3EV push, this way I have more highlight headroom than with one stop push at ISO 6400. This has to be done absolutely in 14 bit mode, the shadows are super ugly and green in 12 bit mode and one can't push the image at all. I believe it is the result of high read noise.
Not to say that D3X is a low light camera per se, or sports camera either, but it hides a mighty engine under its bonnet. For low light and action I use D3S and D4S, but have no problem shooting D3X at ISO 6400 or higher,
if I know I can resample to smaller size.
The same cannot be said of the earlier generation. D2X resampled to 4 Mpix can't still compete head to head with my D2HS in high ISO settings.