Sorry very late reply but life has been mental with job and personal issues so again apologies all round.
The Multiduk is great and works superbly in all weathers especially as a lean to type shelter, combined with a bivvy bag I slept in it in the snow earlier this year and was toastie warm, had an issue with a material defect which caused a rip on one side between two eyelets but Helsport replaced it without quibble.
The Fjellduk is also superb and is used mostly as a watch bag for night time animal Obs, however it works superbly as all the things it is designed to do and also works really well as a duvet when sleeping in a tipi etc, plus I have just discovered this past weekend can be used as a hammock under blanket and a pea pod..... Happy days I am really impressed and for a thermal version of the Jerven bag I would say for the price the comparison is excellent.
If you want to know owt else please ask me.............