"In the case above of DesertCaptain, it was a savings of $5.85. "
Actually the Chase card saved us $7.65 and GB found me a station that was ten cents a gallon cheaper than most of the others in the area ($3.25), for a net savings of $12.15 on a single fill up.
Often GB will find stations that are 20 to 30 cents a gallon less than the name brands along the interstates. When we are on the road doing 400 to 450 a day that is a 45 gallon fill up every day. It is not hard to save $10 to $20 a day in fuel and that will usually pay for our site for the night. :B