 This is my third Hyundai and I have been well pleased with the mileage, dependability and almost zero recalls on all three.  The gas mileage indicator is not a true indication of actual mileage.  When I want to check my actual mileage, I always reset my odometer to zero after a tank fill up.  With the 2018 Elantra, I get around 40 mpg with mixed city/hwy driving and 37 mpg with city only driving.  I now have 5,800 miles on this car.  The aggravating problem that I don't like is the way the ignition key and dash display is wired.  I often park and turn the ignition to lock, removing the key and continue to sit in the driver's seat while my wife shops.  After a few minutes the battery discharge warning comes on and I have to open and shut the driver's door to power down the dash display.  Occasionally, I find the trunk lid open because my key has accidentally bumped into something in my pocket.  This was also happening in my 2013 Hyundai Elantra.  We're afraid to put valuable items in the trunk due to this problem.  The plastic panels at the bottom of the door frames scratch easily and I don't believe they are high quality material.