I bought 3-3/4 tons this year, & had 11 fifty-# bags left from a 4-ton buy last season. I still burn about one 50# bag every 24 hrs. Sometimes varies by a 1/4 bag or so when I crank it up on the weekend. I'm sure that'll go up quite a bit if I end up buying a Harman SF-250, but I'll be warmer!
Just like the Harley -- it gets about 40 M.P.G., but, after cams, a big-bore kit & fatter jetting, it may get 20MPG -- but I'll get where I'm going MUCH FASTER