I just took a group from HIO to Hamilton Montana. We had 12 people, so 6 went in the 980, and 6 in a King Air 350i. It was an interesting comparison... we took exactly the same amount of time (to the minute, according to FlightAware), and the King Air guy told me he burned about 1,000 pounds. I burned about 650...
We were filed the exact same altitudes and speeds... to be honest, I was surprised because I thought the King Air 350 would be a few knots faster, but apparently not. The King Air guy told me he typically sees 295-300, which is about the same as the 980.
It really makes me appreciate the Commander!