I just replied to a similar post:
isb-vs-goizueta-vs-smith-210025.htmlMy thoughts would be that if you can get into ISB, you should be able to break through the top 20 in the US. Georgia Tech is a top 30-40 school graduating 75 people per year. Most of them stick around the South, which nothing is wrong with that but you have to like it to stick around it you won't fit in is the biggest issue. Fitting in will be an issue. I would recommend talking to some of the current Indian students at Georgia Tech or even UNC to check how they like it. I would do the same with ISB - pick their brains about your concerns.
Obviously if you are interested in the US, then you should pursue a school in the US. It is a pretty reliable and straightforward way for moving to the states but again, I think you can do better. Am I too optimistic?
I personally know a few folks who got into top 20 with full scholarship in the US while getting rejected from ISB...