Assuming for the moment that you dont have some unrequited love you havent shared... and you truly are largely indifferent .... I'd elect Stern. Three reasons:
* Brand mgmt is not banking - the pay is not going to be mind numbing out of either program, so the incremental $50K is a pretty meaningful savings.
* The career options coming out of Wharton, Booth, Harvard, Kellogg, Stanford, Stern, Ross, etc are so incredibly similar that there's little likelihood of material differentiation. Put differently, by and large, the same companies recruit for the same jobs at roughly the same pay at all of these programs. In a year when you are sitting at Genentech interviewing, the guy next to you will be from Kellogg. The girl ahead of you from Ross. The guy down the hall from Booth. Schools like to give the impression they are all unique flowers of incomparable glory; in truth, they are largely the same.
* The extension to the prior point: approximately 2 to 3 minutes after you walk into your first post MBA job, no one will care what school you come from. Stern? Good for you. Wharton? Congrats. Booth? Nice job.
I'd show Wharton the Stern offer, see if they want to talk,.... That said (And this is important), if your heart is set on Wharton, and you think you will regret not going - don't let $50K be the deciding factor.