I can't comment on EK, but i've just returned from LHR-LAX-AKL CHC-LAX-LHR, and i can't really express how totally underwhelmed i am by Air NZ's London based cabin crew. (In C Class).

The crew on NZ2 today were terrible. Total lack of visibility in the cabin, infrequent water trips up and down the aisle... They were even making smarmy impressions of one female pax who had the audiacity to ask for some hot chocolate for her child.

Frankly, it wasn't much better on the way out LHR-LAX either. Why is there such a difference between there and the NZ based sectors?

I'm now seriously contemplating avoiding NZ LHR-LAX permanently.