One of my tires developed a slow leak while on a cross country trip, and I had to stop for air at a Sunoco station in New Hampshire. It was the first air pump I've ever seen that was completely free! And first I've ever seen with the automatic pressure setting.
It worked perfectly. Set it to 36 PSI and that's exactly what I got on the TPM dash reading, which I've compared to a traditional gauge before, so I know it's accurate. Most hassle free air-top up I've ever done.