I had my update done yesterday. A few days before, I had driven the same freeway home and noted the RPMs at 70MPH at almost exactly 2K. After the update the top gear RPM at 70MPH was still 2K. Shift points are higher and the shifts seem smoother. I can't imagine this update would have a material affect on straight highway MPG. I'm sure it will in city/mixed driving though.
2009 Acura MDX Tech w/RES, Aspen White Pearl | Parchment interior