Hi guys, I am not sure if what kind of answers I expect to this or I likely would not have posted. But here's the current things on my mind.
1. I really like the 500mm PF but it is F mount and it feels a bit off buying an expensive lens for an old mount with no guarantee things will improve on future Z cameras in AF speed. 2. Canon just brought out a 100-500mm L lens, I know it will hold up to adverse weather like it is nothing and it'll work without an adaptor on a new Canon camera in 20 years from now.
So I really love my z6 and the f/1.8 S primes and it is a system I would really like to invest in. The 500mm PF I think I would get with a dedicated D500 or D850 body as I pretty much gave a dedicated body to my old 300mm f/2.8 on the Canon side. I almost always carry two bodies, so the shorter range is covered by the Z6 at all times.
Almost all of my shots with my 300mm where ether on a crop camera or on a FF then cropped into 500(ish)mm FOV. So I am pretty confident that 500 is the goto range for that wee fox or bird that just isn't going to let me get closer and I am just as quick bringing up the z6 if something is too close.
So fellow wildlife folks, would you still get the 500mm PF today with all this mirrorless excitement? I think it is less frightening to me than a f/4 just now as I think £10,000 is a lot of money for "old tech".
Edit: Also I don't know much about Nikon bodies so my the D500 vs D850(Which one can keep shooting when it is bucketing down in the highlands and I want that hare) may not be a good comparison. I know one is 10FPS and I like 10FPS and I know I love the IQ out of my Z6 with its 50mm and 85mm Z primes.