I wish I could get 40-45 mpg........never had it happen.....If I run on the slab at 70-75 mph, I'll get 30-34 mpg if I run 80-95 mph It could drop to below 30. I think the bike drinks gas to be honest. I road like a fool out side of Hot Springs Ark. doing 80-130 mph with a local on a BMW 1150 and I swear I watched the gas gauge go down as I road.
The windshield is another interesting issue. I am 6'3" and own a Lg Clearview which great in the winter but I think the aerodynamics is bad on the road. I like the the stock much better as long as temperatures permit.
At 280 I am sure you will want a new seat. Keeping the "boys" out of the tank is tough on a stock seat.
Just one man's opinion for what its worth.
Great bike..........