I'm one of the "lucky" ones, my gauge is fairly close.
I try not to go too much below 1/2 tank, around 400 miles or so, before I am looking for fuel. Maybe it was my time in the Navy, and certainly my time as a firefighter; both imprinted the habit to watch the fuel carefully!
But another big reason I fuel earlier is the generator low-fuel cutoff. Somewhere around 1/4 tank the generator will run out so as to not drain your entire supply. I always want to retain the ability to run the generator, so I always keep a "cushion".
2014 Seneca 37TS
Toads: 2014 Ford Explorer Sport or 2013 Ford Focus ST