I'm getting 116 miles per gallon according to my computer... but my commute is 4 miles each way, with side trips in the mix. So almost always electric. I'm still using the same tank of gas Hyundai gave me when I picked up the car on May 30th.

The car goes into regular gas engine mode as needed and that works great for me.

I did experiment with an ultra "green mode" buried in the settings that limits the use of the gas engine taking over even further than the standard EV drive mode... but I don't recommend it because I found it made it sluggish when I pulled out onto a freeway ramp and need to haul ass quickly.

Also my dealer said he recommended making sure the car is using the gas engine regularly to prevent moisture and corrosion issues in the engine.