In my old house we had a gas fire 4.5 kW, we could not have got an electric fire that big, and could not have had a solid fuel fire as only a flue brick, it was used on coming home, as it was fast heating up the room while waiting for the central heating to get up to temperature, it looked better than electric and the radiant heat resulted in 5 minutes before room felt warm.
However there was one problem, there was no thermostatic control. So there was a tendency for room to get hotter and hotter, and until you walked out of room and back in again you did not notice how hot it was.
But the massive advantage was if we had a power cut, we still had heat, so even if there was a really nice electric fire, would still want the gas one, the house was designed so whole house could be heated by the single gas fire, although central heating has better control, it still needs electric to work, we wanted one fire which will work when the electric fails.
This house no gas, and we have a board in the solid fuel fire with a hole for the AC flue in the summer, it is left blocked off and has never been used, but we have some logs, and should we loose electric we do have a back up.