That is so true! That was the case on the Cessna Caravans and Quest Kodiaks that I flew. We relied on the fuel totalizer, not the fuel gauges.
Personally I want my fuel flow to be spot on. It's my preference to land with 6o minutes of fuel, not FAA's 30 minutes for VFR. I got back with yesterday with ~30 minutes left, but I knew exactly how much would be remaining when I landed.