A few years ago, i'd have said Port Lympne, without hesitation, but they have ruined it and made a lot of it, a no go area. Howletts for me now without doubt. And as for them (PL) having Hyenas, You can't see the Hyenas anymore, unless you are lucky enough to catch the one on it's own as the rickety lorry you are now forced to take rushes past it's enclosure. If it's Elephants and Gorillas you are after Howletts wins hands down, as you can no longer get up as close to the Elephants at PL as you could and they have made one of the Gorilla enclosures (My favourite one.) off show.
Howletts, Howletts, Howletts, until PL reverse their disgraceful changes.