Well it was definitely worth it for our £2k Vi-Spring, and that was the sale price when we bought it in 2016.
It changed it from a very comfortable bed to an uber-comfortable bed, for just an additional 5% cost of the mattress itself.
I would recommend it to anybody. Such a small price and will substantially improve the comfort of any mattress. The reviews speak for themselves, and I can only endorse them further.
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