Interesting as always i love this kind of thing. Thanks for putting up the pics
The Cape buff is done well and from my experience its accurate.
The Water buff is good but it is not totally accurate if you have a closer look at the pics you will see there are 2 Water buff there, the one in the background is much more accurate, the rib spacing on one photographed is not correct, they are not that far apart.
As for the Bison it looks like a younger animal or female, but non the less its clear to see its just not in the same ball park as the 2 Buffalo.