Had my 13 for about three months now. I've been averaging between 43 and 48 or so per charge, and was wondering if I'd ever break 50. Today I had to drive to LA from OC during rush hour, which meant 20-40 mph for around 40 miles. I also found some trucks to draft, and it looked like I was on pace to maybe break 60! Trip back also didn't hit good freeway speeds, so when it switched to ICE I was at 57.1 miles on the charge! Hooray!
On the bad side, since I got to the office later than usual, for the first time all four of the charge stations were taken. I'll check again after lunch.