I recall buying the back magic with the nodules, after Marjolein praised it's efficacy to high heaven. As I have arthritis in my back and shoulders anything, I thought, is worth a try. I found using it therapeutic but, once I had stopped, my back was as painful as ever. If I hadn't bought it from the Q, I wouldn't have had the 30 day mbg and, consequently, would have been stuck with a piece of equipment which didn't, for me, work.
This is different from the back magic which I've also got but I got the earlier one without the nodules. The back cradle is one you put on a seat and sit down on, unlike the back magic which you lie on or sit up against on a chair. But as you say, the 30 day money back guarantee has its uses, though you usually still fork out p&p twice if you return an item, unless it's a heavy item or if it's received damaged.
I've got 3 back cradled. All bought from a poundd shop. Total bill 3gbp. One in the car one on work [SUP][/SUP]chair. One on sofa. I also have the blackmail but hardly use it as physio said was the wrong type of curve for my back.