Hi
@ThomasNotTom , I've been a proud owner of a P900 for about 3 years now. I've produced many pictures I'm proud of, with many disappointments as with any camera.
As many of the reviews online state, the night capability isn't very good (which isn't too much of a problem for zoo photography aside from certain specialized indoor exhibits). I'd say pushing the ISO up to even 800 is a fine choice if the pics aren't enlarged too much.
Of course the zoom is the pièce de résistance. Even without a tripod, I've successfully taken relatively non-blurry pictures at 2000 mm (of course, a rest is always preferred).
The weight is also a huge benefit. I've taken this camera on trips where had I brought a larger camera, I'd be quite exhausted and worn out by the end of hikes. It's very easy to travel with for sure.
If you have any other questions please don't hesitate to reach out. Hope I can help.