In my opinion, the Argentine side offers better views of the falls.
I stayed on the Argentine side (Che Legarto hostel, which was kind of shitty) As for the nightlife, when I was there it was pretty dead. It seemed like everything shut down at around midnight. I didn't see much local talent at all. A small amount of bangable tourists girls were around but mostly in shops and restaurants not so much in the bars. Met some expats living there that said the weekends are pretty good. I was there in the middle of the week though.
Definitely go to the falls if you haven't been, because they're literally amazing, but not a place to hook up from what I saw.
I stayed on the Argentine side (Che Legarto hostel, which was kind of shitty) As for the nightlife, when I was there it was pretty dead. It seemed like everything shut down at around midnight. I didn't see much local talent at all. A small amount of bangable tourists girls were around but mostly in shops and restaurants not so much in the bars. Met some expats living there that said the weekends are pretty good. I was there in the middle of the week though.
Definitely go to the falls if you haven't been, because they're literally amazing, but not a place to hook up from what I saw.