Considering the opening post said the following (bold for emphasis) I would assume it is!
As for my own opinion of the list, it is somewhat tempered by the fact I have only seen the four UK exhibits - that said, I'll be visiting Berlin and Leipzig in April, so I'll hopefully have more to say on my opinions of the exhibits highlighted then.
Of the four UK exhibits highlighted, I certainly agree with three of them - not so sure about the Whipsnade enclosure as (great though it is) I would not call it one of the four best exhibits in the UK. I would possibly substitute the walk-through aviaries at Living Coasts.
For the purpose of the article Living Coasts was not classed as an exhibit as it is the whole zoo.
The broad definition of an exhibit is listed as 'a part of a zoo which is in some way linked, but does not represent the whole zoo.'
Everyone sees things differently, if I were asked to nominate the best exhibit at Chester I would say Europe on the Edge, even though I think the giant otter enclosure is very good.