For me, this was not just about cost but principally about getting of natural gas.
But regardless, it also made financial sense with the prices here in the Netherlands, in the long run. It was quite an investment, but it should pay off in the end.
A m3 of gas here cost (when I did the calculation in February 2022) about €1.78. That has gone up and down since then. A m3 of gas contains about 9~10 kWh of energy. Let's say 9 kWh comes out via my heated floors. That's ~€0.20/kWh.
At that time, a kWh of electricity here cost about €0.39/kWh. That's double the price per kWh, if I don't take the Coefficient of Performance of our heat pump into account, which multiplies the energy output by 3 (even at -7 Celcius) to 5, depending on conditions.
And I have not yet taken into account here that the energy from my solar panels is cheaper than buying it from the grid.
At the moment, prices are better (install was in March after a year-long wait) and in the meanwhile also got a dynamic energy tariff with lower prices on average, so the comparison is harder to make ATM. We haven't had both a for a full winter yet, so we'll see.