Thanks to both above.
I'm not too keen on the Tesco bag because while it is undeniably good value it seems to shed down through its fabric a little too readily.
I'm very tempted by your Cumulus 350 and thinking on it (translates to arguing with Herself) and if it had been the two season bag I would have jumped at it. Otoh, I do sleep very cold and the bag has good reviews. Can you allow me another 24 hours for a decision, please?
Cheers