Started using the Niro on May 15, 2018 and today I turned 37,000 miles. I'm averaging 65-68 mpg drafting over-width loads, sheds etc, and 62-66 mpg drafting over-length loads like poles. Average speeds are around 70 mph on highways.
I'm fairly happy with the Niro so far but I can't say much for the Dealers blatant disregard for the Federal Trade Commissions Bureau of Consumer Protection...
The car has some nuances and isn't too graceful at times but manageable. My most often dislike is the cruise control. I've spent over 20 years traveling for a living and driving just about every type of car rented in the US and some abroad, and this is without a doubt the worst cruise control out there. Specifically the reaction time to Accel/Decel input changes. I've never had issues with a cars cruise reacting to inputs fast enough to maneuver traffic like passing and matching speeds. Until the Niro FE, it takes a few seconds to start reacting and then does so very slowly. It has a tendency to wonder around the speed you initially set. I've witnessed up to a 3 mph swing either direction. Unacceptable performance.
Another dislike is when stopping and going. If you don't let the Niro stop completely before going, it'll jerk a bit as if it's confused. Not a show stopper, just annoying.
The iPhone software is buggy using my 6S. Sometimes I'll have to restart my iPhone to clear it out. Voice text is a bit clunky to use but gets the job done.
All in all, I find the Niro to be comfortable enough for a 300 pound guy with a bad back, to sit and drive 10-12 hours a day and still be able to exit without issues. Prior to needing a car with great fuel economy, I drove an old Town Car and would have never considered a hybrid or electric, unless it was a Tesla. I have to admit that I'm enjoying the Niro for work, even though I do miss my Lazy Boy on wheels.