Dehumidifier energy usage, is it worth the extra upront cost?

Effician

Bought an easy fix Ecoair dd1 last year for a fiver to sort expected condensation/ high humidity problems after a major draught blocking exercise , after a little experimenting i found i didn't have an excess humidity problem so much as a cool surface / below dew temp problem (due to only having the one log burner for heating) in certain parts of the house, which is now mostly kept in check by very low wattage fans appropriately placed.

No need for the dehumidifier so far this year but it's there for a little heating & condensation reduction on the really cold days, just have to be careful as i find too low humidity worse than slightly high ,health wise.

Freebird53

I would be interested in the Litres @16-18C (my likely room temp) per kwh, a unit of whatever type could extract.

As well as the length of warranty of said unit.