Agree with Zol, neither the co-ordinator directing pax to the cars nor the driver seemed to care or check how many pax in the car so long as all pax and the luggage fit comfortably in one car. If they did they didn't raise any eyebrows. Makes sense to me since it doesn't matter if the car checks-out with one pax or four. Still one must appreciate EK for this -- it is generous.

Might be helpful if everyone doesn't go up to the desk together to pick up the voucher. That might potentially invite questions from the staff who issues the voucher.

Didn't use fast track as we have e-gate but in hindsight we should have asked for it. The e-gate queue was longer than the fast track! So well worth asking for these.

I would highly recommend you always pre-book the car. On a recent trip to JFK, I did not and guess what? They didn't have an extra car available!