I looked at this route also. When I was in Argentina in 2004, the exchange rate was $1.00 = ARS 3.4. Now it is something like $1.00 = ARS 107.
I think there still is an AMEX Centurion Club in EZE. The other wrinkle is that I think you have to pay a departure tax separately at a window in the main terminal before they will let you proceed to security (the local government does not trust the airlines to collect it and remit it).
The best cabs in BsAs are the "remisas", radio dispatched cars. There is a public transit train that runs to the town of Ezeiza, but for some reason does not go to the airport.
The standard of food is quite high in Argentina. I hope you enjoy yourself.