FYI, I have the coolbox in my LX570 and I absolutely love it when on long, overlanding trips. I tend to travel in warmer areas when overlanding and it is awesome having cold drinks readily available without having to get out, swing my hitch mounted Mountain Bike out of the way, open the liftgate, slide the fridge out to get a cold drink.
I understand that it is not for everyone and consumes valuable cargo space but I'm getting the Premium package, largely in part to have that coolbox....plus all of the other goodies.