I like Taxi Ezeiza. Usually the ones that work inside the airport are very good and are cheaper than Tienda Leon.I believe Taxi Ezesia may be as good or better an option. There is a desk inside the secure area and one outside the secure area located in the terminal near the exit of the secure area - the latter has lower prices than the former (go figure). Both take plastic.If you have a lot of bags, ask for a taxi "familiar" (an SUV type).
I thought it's difficult to get an Uber from the airport and it's possible that taxi drivers will harass/attack the Uber driver and passenger?