Can someone please advise thoughts on the Owlet Sock device? I understand it's not specifically recommended as necessary but wanting to know if it's of any use- there are so many opinions on each side

Red Nose has the following information about the use of home monitors.

There is no scientific evidence that using any type of monitor will prevent a sudden unexpected infant death.
A monitor may be very disruptive for the family and some families find using devices can increase anxiety.
False alarms may occur if the baby is breathing shallowly, rolls off a mat, or there are technical problems with the machine.
https://rednose.org.au/article/home-monitoring

The use of a monitor has not been part of the Safe Sleeping message & the subsequent 85% reduction in infant death.
However, for some families the use of monitor may be helpful for reducing anxiety.
However, monitor is no substitute for safe sleep recommendations.

Many parents, aware of the risk of sudden infant death and wanting to provide the best possible care for their child, may consider the purchase of a home monitoring system for their baby.
This may also include parents who are expecting a baby following the sudden and unexpected death of a baby previously.

In a very small number of cases, health professionals may recommend the use of home monitors, where their use can be helpful for babies and families.
All families who have a monitor recommended for their baby require baby resuscitation training (Cardio Pulmonary Resuscitation Training)
https://rednose.org.au/article/home-monitoring

It is recommended that all families who choose to use a monitor also attend CPR training.