Apparently it is further to get to the United Center from hotels than Indy and Bankers Life. Instead of five minutes it is more like thirty.
I have been to the last 2 B1G tourneys. It feels like less of an event in Chicago. Indy seems like it goes all out, but I guess Chicago is a much larger city so that makes sense. In Indy EVERYTHING is right there near the arena. Indy is the perfect setup for events. In Chicago it takes about 30 minutes to get to the United Center via public transport. Everything is walking distance in Indy. Bankers Life is more of a basketball centric arena and has better overall sight lines - it's also newer. Not much around the United Center in terms of food/nightlife/hotels and there was one beer tent in the parking lot.
Overall I'd say it feels more at home in Indy but Chicago is one of my favorite cities and it is the conference headquarters and has a larger arena. Can't go wrong with either but I'd give Indy the nod.