If you don't mind the trip then I'd def say West Mids.

Last time we went they had a "baby" giraffe and we were feeding several giraffes through the sunroof - that was amusing to say the least

They got white lions - and a couple new white lion cubs now as well.

The tigers are fenced in but the normal lions are loose where you can actually drive through.

They got the rest of the stuff like the sea lions and reptile house as well once you've had enough of driving around (you can drive round as many times as you like).