Im allergic to feathers...
the 2 i had as a child are now here at my house... they must be 27 / 20 years old respectively
they have been washed in a normal washing machine at least yearly at 60C... they are still as goos as new IMO... and if / when i have children i see no reason why i wouldnt use them for them....
on my current bed i have 2 duvets (summer and winter) they are both cheap duvets, and less than 2 years old... i tore the casing on my summer duvet while changing the cover (I have no idea how ) so it hasnt lasted as well and im sure will be binned in a few years!
im being more careful with the other one...
but next time i plan to buy ones with a cotton cover rather than that papery type stuff that is trying to be material!