https://pregnificant.com/products/baby nest-deluxe Hi, I was just wondering if these and similar products are SIDS safe?

Red Nose does not promote/endorse any brand name products for infant sleep.
There is no “SIDS safe” sleep product.

There are a lot of portable sleep spaces on the market, which do not meet the Safe Sleep guidelines, mainly due to a number of safety concerns about pods & nests & on how they are used.
These include soft, padded sides & soft base & minimal height on sides.
Product Safety recommends sides of a bassinet should be 300mm high
https://www.productsafety.gov.au/products/babies-kids/kids-furniture/bassinettes
Some of them are designed specifically for co-sleeping, however the baby is still at risk of adult bedding being pulled up over the baby’s head & face.

Red Nose recommends the safest place for baby to sleep is in a cot that meets mandatory standards (or a bassinet that meets guidelines recommended by Product Safety Australia)
https://rednose.org.au/article/what-is-a-safe-sleeping-environment
https://www.productsafety.gov.au/products/babies-kids/kids-furniture/bassinettes

Red Nose also recommends to avoid using anything soft or padded in baby’s sleep environment.
The products you mention, & most of the others have soft padded (cushioned) sides.(similar to a cot bumper)
Soft bedding is dangerous in a cot and should not be used. Soft bedding includes pillows, quilts, doonas, soft toys and bumpers. Soft bedding may cover the baby’s face and obstruct breathing and/or cause overheating.
https://rednose.com.au/article/at-what-age-can-i-introduce-cot-bumpers-and-pillows

Lullaby Trust, our colleagues in UK, provide the following information about pods & nests:
Pods/nests Pods or nests are a softer type of sleep surface sometimes used instead of or in addition to a mattress, with areas that are raised or cushioned.
When sleeping, babies shouldn’t lie on or have anything soft around them, particularly their heads, as this can cause them to overheat and increases the risk of SIDS.
Soft, squishy materials can also cover baby’s mouth and nose if they are pressed against it.
https://www.lullabytrust.org.uk/wp-content/uploads/Product-Guide-a-guide-to-buying-safer-sleep-essentials.pdf

Red Nose also has the following information about “sleep products” in general.
Not all products designed for babies are safe. They often attract parents with the promise of making sleeping, teething or carrying easier. But without safety regulations or proper use guidelines, they could cause a serious incident.
https://rednose.org.au/article/baby-products-you-dont-need