In reading your review of the place from your 2011 summer road trip and looking at your pictures, I really struggle with how I feel about this place. Hunting certainly does have a legitimate role in some forms of conservation (e.g., wetlands conservation by duck hunters), but I don't see any educational value in endless walls of mounted heads. This type of display seems completely different to me than what Theodore Roosevelt and his ilk were doing when they collected scientific specimens for museums and display galleries were created showing full specimens in recreation of their natural environments.
David, this is exactly what I meant when I talked on the hunting thread about faded trophies. If you do come to the UK, a trip round many country houses will bear evidence of a family member's enthusiasm for big game trophies in the days of Empire. Very few will serve any educational benefit whatsoever.
(One honourable exception is the Powell Cotton Museum in Kent; with a car, this could be fitted around a trip to either Howletts or Elmley Marshes, in winter/spring one of the best wetlands close to London).
I should have added that there is some morbid interest in visiting the Musee de la Chasse in Paris, which has the only mounted Kouprey's head that I know of. I fear that it's a trophy destined to retain its uniqueness...