$8 IKEA feather cushion inserts

UPDATE: I ended up buying a couple of these to try a few months ago... I am afraid I don't like how they lose their shape and need to be re-fluffed ALL the time :(

All our Rapee cushions have collapsed after 2 years. I would like to get some better quality inserts that don't collapse... Has anyone had any experience with IKEA FJÄDRAR Inner cushions filled with waterfowl feathers? They are $8 for a 50cm x 50cm insert. Would love to hear your recommendations for good quality (not too expensive though) cushion inserts :)

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