525 HP C13 in 45' Beaver Patriot Thunder flat towing Mercury hybrid. Over 20k miles coast to coast and back, and border to border we average about 48,000 lbs down the road and 25 MPG with cruise usually set to 62-63 (except in Calif where sometimes I can't get into and stay in high gear). The hybrid gets around 44 in town and coach about 6 towing or not, thus averaging about 25 mpg when some smart Alec asks. Hot head winds with Gen running may drop coach to 5.5, good consistent tail wind all day and may bump coach up to 6.2