I agree with yepsee on this one..
I got ISB but am attending Columbia..its a very subjective decision. i wanted some things from my mba that isb could not give to the same extent: international exposure, great network, global branding..huge network.. its like IIT vs. MIT.. with so many engineers here im sure you'll appreciate the analogy
also like yepsee said its very dependent on the job u want... ive been in ibanking and tend toward staying in it post my MBA.. and which banker can give up a shot at working in manhattan

also, i know a Lot of ppl at isb... alums, students and aplpicants!! i know the school very well because a lot of my seniors from work are from there.. and friends too..but wasnt very keen on the culture..
columbia is a Huge investment for lil ol' me - but its an investment, not an expenditure

but like i said its a very personal and subjective decision. you have to take a lot of factors into consideration.