Well i stayed in Postel Carretas last year when i went on an expedition 2 patagonia in south america. on our last 3 days we stayed in Buenos Aires, and were told we would be stayin at this hotel. The rooms were of a high standard and it was a small walk away from amazing resturants and a hugh shopping area.
The pool was always nice and cool, which was gd because of the extreme heat in that country. All i can really say is if you are goin 2 be travellin to Buenos Sires give this hotel a go. you will not regret it.