Yesterday I did my very first fillup:
370 miles - 8.16 gallons = 45.34 MPG
The in car calculation was reporting 48 ~ 49 MPG, so it appears to be a little off on the plus side.
I didn't fill the tank initially, dealer did, so not sure if they "filled" it although when I got the car the gas was reporting full. When I filled, I didn't top off, just to first shutoff. To get at the gas cap, push the gas cover into the car and then it pops open. There isn't a release from the inside, I had to consult the manual since previous cars always had release from inside.
Driving conditions: Mostly Highway (Springfield MA to Hartford, CT and a trip down from Hartford to Plainboro New Jersey). The trip to New Jersey it was pouring rain. Outside temps 40-70. New England is hilly, not too many flat spots, mostly up and down. Some cruising around town. I don't do any of type of hypermiling (no shutdown while crusing, no nuetral, etc), just normal driving, although it seems I drive slower that 98% of other drivers out there.
Eco mode always on, maintain 55-65 on highway depending on traffic and conditions. I've used the cruise control, but really just to try it out.
Looking forward to improve on initial numbers as the car gets broken in and it gets warmer.