Should be interesting what happens with the ex ZFV-EWR-XYZ flights.
I've had my fair share of frustrations on the Airtrain, nothing major, but the seamlessness of having the airtrain station right at C2 and then getting off steps from the platform is quite nice.
It beats getting a receipt just to hail a cab at EWR, taking the 15 minute and something like $12 fare to Newark Penn then lugging your bags up the steps to the platform. I have done that several times because of the better availability on Amtrak to NWK than to EWR.