This is a very useful product and is much needed especially nowadays with necks and shoulders getting lots of strain with device use and poor posture.
This is rigid and can be used in two ways, one which gives a lighter stretch and the other which stretches more.
It definitely helps but probably needs to be used regularly over some time to start providing benefits. You need to only use it a few minutes everyday. The stretching does ease pressure on the neck and reduces aches and stiffness.
It can seem pricey for a piece of plastic but with the benefits it provides it becomes cheaper than going to a chiropractor or Physio. Overall it is helpful.