I've been checking the images you linked, which are very nice as always, and I've seen than in most of them you are using high F/stops. The image quality is very good even in the corners but I am wondering what happens when you use open f/stops.
I've been checking some images by Todd Winner (at Nauticam's website), and even at low res you can see that at F5,6 the corners are not good. If this is the case I think is a very expensive investment if you must use a very old lens behind, which has slow autofocus and you are bound to use closed f/stops. So the only real avantage would be a bigger zoom range than with any other lens... Am I right?
There are more example shots from WACP on my website now - to show how it can be used. I have over 100 up there now, they are sorted chronologically, so newest are first: