a 3rd party mechanic? an Infinity mechanic?
I only ask because that is such a new and techy car that having a dealer give it a once over is always a good idea for a big purchase.
Did you look at the milage rating for the 2008 model? prior to 2007 (IIRC) highway milage was based on 77km/h, and city based on something stupid like 40km/h