Milk savers. Has anyone used these? Opinions please

Question

Hi, I will be a ftm in May 2016 and have come across these online and am very interested but I don't know anyone who has used them. 
I'm after people's experiences with them, good and bad, to help me to decide whether to use them or not.

Answer

They are only meant for catching the letdown from one breast while you feed on the other. Not daily wear. Still need breast pads for that. And they only come one in a box.

Answer

I've never seen these before. Does it say how long you can wear them? As in will the milk spoil? Curiously following!

Answer

My sil tried them but said she couldn't wear them out of the house due to they leak.

Answer

Just had my shower today and my cousin who had two kids mentioned these. She said she'd loved them! I might try them out :)

Milk savers. Has anyone used these? Opinions please

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