it very much depends on the patient - thing like symmetrisleep are good if someone can tolerate it, but it can get very warm and take a bit of 'weaning' into it.

You have to know what you are tryng to achieve before even looking at specialist systems. You can rig up most postures with pillows, wedges and rolls first before resulting to what is a very expensive piece of kit.

I would be a bit skeptical of the research that come out of the companies themselves but looking and neurophysiology you could answer your own questions.