The lack of sensitivity to a lower fuel level, while not at all uncommon, is a pain in the neck, IMO. As others have said, you have to make an estimate of how far you can go after the fuel gauge switches to count-up reserve. That requires you to know two important details: How much is left when it starts flashing on reserve, and how many mpg you can expect on that amount.
Neither of those things are particularly hard to determine. Just fill the tank immediately when it switches to reserve a few times and subtract whatever volume it takes to fill it from the 6.6 gallon tank capacity. If you find that it generally requires 5.2 gallons to fill when the gauge starts flashing (mine does), that tells you that you have another 1.4 gallons in reserve.
Most of us keep fairly regular tabs on our fuel mileage to stay aware of how well the bike is running. There will be wide variations in mpg based on altitude, weather, and especially how much fun you are having at the time. But, knowing what you can expect if you baby the throttle to get to the next gas station is the key.
I generally can get 44-46 mpg in grandpa mode, so my reserve range of 1.4 gallons gives me about 60 to 65 miles. To keep my own stress levels in check, I generally try to hit a station within 50 miles on the count-up.
Oh, and... YMMV.