I actually find the High Shutter speeds to be rather redundant with my work - in a majority of my wildlife photographs I have used fill flash in some form, and that means hand holding a 200mm+ (300mm on APS-C) lens at 1/180th flash synch speed of pentax cameras* - I never use HSS because it kills the range of the flash too much. I use a
Sigma 100-300mm f/4 APO EX DG for a majority of my work - unfortunately that lens is discontinued.
the K-7 is very quiet in terms of shutter noise, most animals don't notice it even when I am really close. Also I have been experimenting with Wireless flash for my wildlife work, because there is this tendencey for wildlife photographers to use the flash mounted on the camera and this causes the images to have the same "look" which gets a bit boring after a while.
*and I sometimes use even slower shutter speeds than that to balance flash with the ambient light, and for moments like those a good monopod is essential.