Depends on how you ride. If you ride the same lines at the same speed as your n/a buddies, you'll use about the same fuel. If you just shoot straight up the slopes, then sit & watch while your n/a buddies pack down a path & finally make it up after 20 minutes, then you'll use a lot less fuel. But you, young grasshopper, will find something a little steeper & deeper... or take off from a standing start at the bottom of the hill (instead of getting that 30mph n/a run at it) so you trench in a little off the start and waive the skis in the air all the way up the hill... and more fun = more fuel. At 11psi, I normally use about 30% more than n/a sleds in my group. I'd like to use 50% more... but I only carry 2 gallons extra on the tunnel so I normally have to tone it down to n/a levels for the last hour or two of the day so I don't run out of fuel.