I have used the underlay from these guys for a while (maybe three years) and found it really did make a difference to my sciatica, so, despite my natural skepticism, as far as I'm concerned there is something that works here.
Gave this as a gift for my partners mum (she has an underlay as well and feels it makes some difference). She was delighted. Was well-made and the guide/instructions were very comprehensive.
Found lots of other spot magnets but they all seemed to just come as a pack of magents with no other information so didn't seem much good as a gift.
Not heard back yet on the effectiveness but as a gift anyway it was perfect.
Well made, good value