I just opted for the snugpak quilts, cheaper and should go to -17C with base layers if you set it up correctly according to folk who used them, they work when/if wet better too. Waiting for mine to arrive now after getting feedback in a similar post i made the other week (should be on my user profile maybe?). The down used at uk hammocks is plucked off live geese, kinda felt a bit wrong to enjoy nature by abusing it, a bit like littering but worse really. It is basically bulk vs cruelty, you can do extra leg work to keep the down dry.