A big collecton is great to us zoofans, no question, but to have better exhibits for the animals, is much better for the animals, which have to live there.
I would have to agree. I have seen photos of their Red-capped Mangabey group. They live in a grass paddock with a small pile of old/worn branches/logs in the centre. I am amazed anyone can willingly display forest-dwelling Primates like that and think it is acceptable in this day and age.