I have been considering purchasing the Stretchsit Cushion, but I want to make sure that I will benefit from it. I have also been considering buying an inflatable lumbar pillow, such as the Therm-a-Rest Lumbar Pillow, which has been very well liked (http://www.amazon.com/Therm-A-Rest-Therm-a-rest-Lumbar-Pillow/dp/B004IIRSAU/ref=cm_cr_pr_product_top).
Dr. Stuart McGill, one of the world's most prominent, if not the most prominent, scientist devoted solely to low back studies, suggests on his website that sitting should be dynamic in nature, with postures changing so given tissues don't get overloaded with stress. (http://backfitpro.com/lumbar_support.php). He notes that although slouching (lumbar spine in a very flexed positon) will stress the discs too much, sitting up too straight for too long will activate the psoas and back extensor muscles, basically crushing the spine over a period of time.
I like Dr. McGill's idea of making sitting dynamic, but I wonder how the stretchsit cushion plays into this. I'm honestly considering buying both products, but before I do so I want to get some opinions on what the best solution might be.