I've been driving my Ioniq for 3 months now, in New Zealand (temperatures between 10 and 30 degrees C), in town, on rural roads, highways and motorways, up to a speed of 100km/h. So far the promised range of 200km has been spot on - 1% of battery charge means 2km, and I can rely on that. My efficiency is around 8km/kWh, a bit less if I turn the aircon on. Can't complain - it performs as promised.
A recent test in Germany also confirmed that the Ioniq provided the best efficiency of all tested EV cars - around 14kWh/100km, which is a bit less than mine, but conditions were harsher and speeds were higher in the German test scenario, so that explains that.
Hope that helps.
Cheers from NZ