I have found the MPG calculation to be very accurate, but I believe the fuel gauge and DTE calculation has issues. There is another thread about it here. The needle doesn’t seem to start going down until 100-150 miles, and if you park on a slope for a while, the fuel level and DTE doesn’t seem to fix itself when the vehicle levels out.I'm interested to see how it really does on fuel mileage. I've put 160 miles on it and the computer shows 35 mpg with about 425 miles of range left. The gauge just got down to the full line, which is weird.