last i ran something, i was racing my sister in her 03 M3 SMG, she was in S5 mode (only 2 other modes faster than S5 in the M3 which are S6 and launch mode). the X5 beat the x3 off the line, and pretty much was neck and neck with it to 100mph. I'm guessing the time was low 5's. Conditions were good (below 70 degrees) and I was running 97 octane in the X5.

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2008 E82 135is JB2 Alpine White / Lemon
2008 E90 335i JB2 Monaco Blue/Grey
2007 E85 M Roadster Black/Black
2006 E60 550 w/ M Kit Silver/Black
2003 E46 M3 SMG w/ VMR V715 19's Blue/Black