That's steady highway cruising. I see numbers like 23mpg on your links, which is about what I'd average around town on 93. E30 means a 10% hit and puts me around 20mpg. Most of my trips are on 45-55mph roads, but with stops, and probably only ~15min average, meaning the couple minutes of warmup takes a bigger bite.
On ~25-30 mile drives around here, I'll break 25mpg even with E30, probably because the handful of stops are offset by the lower wind tax of cruising at 50-55mph, and coasting where I can.
