I used to have underfloor coil type. The coils were only in most foot traffic area so it doesn't waste energy heating up tiles say over by the dinning table, just the living area and bathroom etc...
A big factor will be how the heating is controlled from the power company and what your unit price is. Our's was on a night only meter that was half the price of the 24 hour meter and less than a controlled/boost meter.
Anything other than a night only meter is a bit of a power waster. You end up switching a heatpump or a heater on during the day to be really warm... then the thermostat clicks off for the underfloor and you end up cold tiles.
So we'd set the thermostat in the living room to the highest (32degrees) so we used it as a night storage heater to get the tiles as warm as possible on the cheaper rate and to start warming even if the living room was still warm from people using it a few hours earlier.
Many houses in the 70's and 80's had underfloor heating installed, the old coil type in the slab, and probably without any insulation under it. But many people rarely used it due to the high heating cost involved, and that was back when power was cheap. I do wonder what the point is of putting underfloor heating is these days, apart from to take the coldness off the tiles in a bathroom, where wearing slipper would fix that. Wouldn't i be better just not to install tiles, and go for floorboards or lino in wet areas.