When I had my car coded, I had the default changed to Eco Pro and I was very satisfied with it. Unless it's a very warm day (uncommon in Santa Cruz), I never miss having the incrementally strong A/C settings, and I like the stiffer pedal feel which keeps my from being a leadfoot. However, everytime I take the car to the dealership (generally to get a fault code reset and not due to regular maintenance), the car gets reset to factory specs and I have to drive 60 miles to my "neighborhood" recoder.
However, something odd happened the last time I took the car in for servicing. I had a message on the large screen telling me that my airbag system was kaput and that I should only drive with seatbelts on (duh). I loathed the idea of getting service at the dealer due to the loss of custom coding. I picked up the car two days later, and (yay!) the option to turn on the Range Extender at will has been retained. The Range Extender option does not show in the menu, but since I had a dash button set to turn the REX on and off, that function still works.
So, I am not sure how this happened, but not all of the custom coding was wiped out. Not as sure about the expanded gas tank option. I need to figure that one out more carefully.
Chuck