I've been in ORD for 3 months so far and love it. That being said, I live here and have sworn off commuting (hopefully) forever.

I'm junior 737 and have held lines the entire time. They're a mix of 3 and 4 day trips with around 14 days off for the month and mid to upper 80's credit. Typically not commutable on the front end, but finish with a red eye. Very commuter friendly on the back end of the trip.

If you're coming from EWR, the trips aren't as good. Purely my opinion... Nothing beats being based at home, though.

And just some food for thought, I am super junior here (mid 80's%) and still holding decent lines. I'm guessing local guys probably bid reserve, so there is plenty left over for us bottom dwellers. I did bid reserve for December and have only flown an out and back so far. Easy living.