@almarg et al These warnings pertaining to pacemakers, hearing aids and metal implants are applied to induction stove tops and I have seen some microwave ovens with similar warnings.
Items sold as medically directed alternate therapies that use magnets are a focus of our Medical Association who say these deserve appropriate warnings.
With regard to the OP subject, IMHO, I cannot fathom the logic of laying down USD$600 (AUD800) on a mat that has no information forthcoming, no facts, figures, pictures, just the usual enthusiasts gushing about a blacker sound floor; having gushed about the same results from mega-buck fuses, wall plugs, Graphene treated coagulant fluid and so on, such that the black sound floor could not get blacker or the change be any more audibly discernible unless measured with a meter.
Not a peep about factual figures about system benefits, just an empirical love in. I looked on the web and found naught.
There is nothing prejudicial about my comments, as these are my own observations, my opinion, as worthy as anyone else's.