I've owned an Ioniq and just traded in a Kona, and I think we've been spoilt by the Hyundai GOM and heat pumps. The GOM was accurate to within a few miles (which I relied on a couple of times at the end of long journeys). With the MG, I now ignore the GOM and look at remaining % battery. The MG algorithm for calculating charge seems to have difficulty putting all the variable parameters together. On my long trip on Tuesday, the HVAC was set to 22 Celcius, fan on 4, and towrds the end of the journey I was getting 3.0m/kWh.