Stetchmate Back Stretcher

There’s no doubt that giving your back a good stretch can have some useful benefits but is the Stretch Mate Orthopedic Back Stretcher the answer? It says it:

Conforms to the spine’s natural curves. Realigns and supports the vertabrae. Eases muscular fatigue and tension. Enhances flexibility and improves posture

Ok, but isn’t just a curved piece of plastic that you lie down on? Maybe that’s all you need really? The reviews seem a bit mixed but mostly positive. Anyone out there try this out? How does your back feel now?