I use either Mobil, Sunoco, BP or Gulf 93 octane here in NY. I had to put one tank of 87 in the car (actually half) as a result of the Sandy nonsense, but now we're fully back on a 93 octane diet. I notice very little difference in performance.
Merry Christmas all.
2011 535xi Cold, Prem 1&2, Convenience, Driver Assist, folding rear seat