I'm after some blinds for our living area, we've got 3 large 1.5 x 2.1m windows street-facing, but there is a reasonable harbour view also that we'd like to maintain if possible.

I see these advertised as allowing one-way visibility: https://www.kresta.co.nz/custom-made-blinds/roller-blinds/sheerview-roller-blinds/

However the likes of Bunnings/Spotlight (in Chch) have much cheaper offerings.

Does anybody have any experience with some of the cheaper products and know if there are any that provide this kind of functionality?