Don't forget eco mode- it really helps the mpg. Even though I have a Guhl reflash, on long trips, I keep it in eco mode, to shorten the number of times i have to stop to refuel- it really does help.
And, I am sure there will be some who say if you care about mpg, you shouldn't buy a bike like this but hell, when the bike is loaded to the gills, I am on a long trip and I am wearing my full suit, the last thing I want to do is pull over, take the gloves off, swing that boot wearing foot over the bike (without scratching a bag), get the beast on the center stand (to get max amount of fuel in tank), find gas key, find cc and fuel up.