James it simply depends what you want to use it for. In my van I use it to run either a Philips Air Fryer or a Microwave and of course it's there for anything else I might need it for.
but
because I have it I can also run the house heating (boiler and pump) independant of the grid and between times perhaps use the washing machine, or tumble drier, or the oven.
so overall they are useful pieces of kit....mine is a Honda 2kw.