Probably ORD sense most everyone what's to move west. Our lines change regularly but in ORD there's almost 2.5 times the flying than in IAH and almost 4 times MSP which means more chances to fly in ORD. Plan on lots of 4 days with pay values between 18-25 (average of around 20ish) and a variety of report and release times spread throughout the day. Bottom line, nothing you can plan on until you get senior.