It did good business not record breaking. Shankar made a very loyal remake. The ones who have watched 3 Idiots & loved it would find it hard to "appreciate" Nanban fully. I am one of those.
Nanban had Shankar's trademark songs, the kind only he visualizes & shoots showing Ileana at her gorgeous best as well as hot. The problem was we have loved 3 Idiots & the performances in it so much that we never watch Nanban as a standalone film but compare every frame of it. Vijay's imitation of Aamir throughout is a disadvantage too.
Since I mentioned the songs, watch them when you have time. Tamil should sound like an alien language but visuals of the songs will definitely make up for it.