Absolutely horrible selection at ORD yesterday evening, Thursday, 2/6. Had an X5 reserved and the app showed me that I was due to receive an X5 with 50,000 miles. I didn't accept in the app because I wasn't going to drive a car that has 50,000 miles on it on a two week roadtrip. The woman at the desk was very, very nice but explains there was nothing she could do. She looked and looked and couldn't find an alternative. I told her I was basically willing to take anything that was new. She had nothing.
I asked her when they retire cars and suggested that this one was getting a little old. She told me that cars are retired at Sixt at 600 days and this particular X5 only had 23 more days of service on it. In the end, I cancelled at Sixt and reserved something on the spot at National (where the selection was also pretty terrible in Executive aisle but all the cars were almost brand new).