One more observation on the Amazon site. All 3 have been in the top ten in the magnetic category for months now. Every once in a while they would pop up in the much broader alternative cat. Both the knee and back have been steady members of the alternative cat the past two weeks. The back reaching into the top thirties and the knee hanging in the eighties. These categories are updated hourly.
That's really great. I started doing the same exercise as you did in the beginning but stopped after a few months. Daily it was only a couple (0-3 max) of patches. I remember wondering whether these were only internet sales or whether the sales from the shops were included as well.
Thanks for the Boots info wyatt. It is clear that word is spreading in England about an effective non drug, non addictive pain management tool called Actipatch.