About how long does it take to get from EZE to central areas of BsAs? What are the good options besides taxis. I speak fluent Spanish, so the language barrier is not an issue.

I'm going to see U2 on March 1st can get a Varig flight to get me to EZE at 17:55, if on time. Fortunately (or unfortunately), I have a 5h layover in GRU, so misconnecting isn't really a major threat. The show starts at 22:00, so I've basically got 4 hours to get out of the airport to my friends' apartment and out to the show. Is this an unlikely time frame?

Also where is the Estadio River Plate? Is it far out of the city center?

Or if anyone has 3 or 4 tickets for the 2nd and wants to go on the first, so I can avoid all of this (mild) craziness.