Nikwax Down proof?….. anyone ever use it?

[Flyrod]

So apparently we can make our regular down wear water repellant just like the major producers are doing now.

Has anyone given it a go and what is your opinion on this stuff? i have a few pufffy's that would benefit from it, but would hate to discover in the field that it was the wrong direction to go.

Thanks.

this is the product in question..
http://www.nikwax.com/en-us/products/productdetail.php?productid=269&itemid=-1&fabricid=-1