Update: mpg is up to 24.6!
They must be braking in.
I had a lot of 70 mph and stop and go on this tank. Both of those take fuel. I don't know how this tank will do. I filled up and it started missing and running like crap. I suspect bad fuel and will talk with the station tomorrow to see if anyone else has complained.
I used to run used tires, but had a lot of problems with them recently, so I went back to new tires. You never know how a used tire was treated. I once picked up a set of new Marathon trailer tires and put them on my truck. Those tires were very light, had decent traction, and lasted a while. I wore them down to nothing and finally blew the tread on one of them with a football sized bump. They handled like they were on rails. I bought new after that. Cooper StMaxx. Great tires, but a bit heavy when new. The tread was almost an inch deep. They have lasted me over 7 years and are still going. That comes out to about $100/year.