I did 2 classes at UBA and didn't really like them, they were too easy and progressed pretty slowly, but they basically refuse to put you into the next level, also the second class was almost identical to the first, so if you just want a basic review of something then do it, my friend liked the higher level so perhaps they get better if your Spanish is pretty good. They also offer night classes in their Palermo location. Definitely pay by CC, last year they had strikes and classes were cancelled and or delayed. Took my friend 4 months to get his CC refunded, when he first asked they said the govn't has the money...aka too bad so sad.
Also last year the intensive courses were 1,600 pesos and your second class, if you take more, was 1,160