I am glad that your car was fine and had a nice service.

Actually, I returned mine also, but did not received the car we booked but been downgraded... without a refund/compensation. I consider x3 lower than a 5 series, as the car group shows, and the msrp shows, but they claim it is not a downgrade.
In the lot, there were couple X5, asked if x5 be an option, they said no because it is booked. Well, then where is my car booked? I would never recommend Sixt to others with this experience. They even did not apologized for the inconvenience.

Also later, they promised to provide a compensation of some sort, in a refund, but they never told the exact amount, even in estimated amount, and they said I will need to check with Sixt SFO(as it was one way) during return. Well, in SFO, the agent told us there are no changes in the charge. Nothing was done from LAX. This is seriously, not a good business practice.

For the condition of the car, this was another big disappointment. The car was quite used, mileage (if I remember properly) wise and condition wise. I am not fully sure about mileage so I will save my word here but I can definitely talk about the car's condition.

The car had scratches all around. The trunk area had biggest paint damage, which never felt good. Also, interior was not clean, especially near the door handle, and the windows. The door handle areas had a big dark stains, which really felt dirty, and the window was very dirty, most sides were stained, and while all the windows were dirty, the rear left window had a remnants of big sticky paper there which seemed like a paper sticker to new vehicle sometimes which is really disgusting for a premium vehicle.

For mechanical wise,the wiper fluid was low, the engine or some part related to driving made some weird noise. I am quite sure that it is not a normal sound as I own/owned couple bmw, including the x3, and I never heard it. With a barebone options, I really had a bad experience.