For the years that site has been up, it's never been much good for anything buy regular unleaded. Only time I buy regular is for the lawn mower. Everything thing else is diesel and premium. Sucks to be me if I'm filling the 45 gallon tank with diesel in the truck and 65 gallon tank with premium in the boat. The wifes car is the easiest to fill with premium with the least amount of tears.
Went to Oklahoma last weekend and saw 87 octane as low as $2.48 and premium (91 octane in Ok) as low as $2.99. Diesel was no less than $0.70 to $1 higher than premium anywhere I looked.
I saw $2.72 for regular at a gas station in south Austin. You know it's probably only going to be like this for a week, maybe two, before it starts creeping back up.