I don't really know, but I suspect that the NHS ones will work as well as many of the mid priced private ones, but will not be as discrete. To get markedly improved performance you would have to pay a significant sum.
Huge win for Andy Burham, Reform a distant second - where to now?
. When I say that my OH is muttering it is true - his PD has affected his voice - so I start the day with pardon and finish the day with pardon!
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