Neat stuff! 25mpg at 100 mph is very, very good. Did your fillup mpg actually agree with what your digital display told you? Obviously, you couldn't run an entire tank at 85mph, but in general did your display mpg match your actual calculated mpg?
I ask because my display is always about 2-3 mpg optimistic, and my general impression is that the digital displays are usually optimistic-across all brands/makes.
I did a recent trip, and my digital numbers were roughly what yours were-68mph 49 mpg.
Thanks.Charlie