I rented a BMW SUV at Sixt at a major airport on the East Coast. It was my first time renting with Sixt. Since I had never rented with them, I asked some questions while picking up the car... the guy at the counter told me that it was okay to fill up the BMW with regular gas.... I could not tell if he was kidding or not.

During the 3-day rental(about 600 miles of driving), I filled up at Costco a couple of times, with premium gas, just like what I always did with my own BMWs. Just before returning, I topped it up with BP premium gas(only gas station near the airport)

It got me wondering... what kind of gasoline does Sixt use when they add gas to their BMW fleet?