While tidying out a cupboard today I came across a bar of old Cadbury’s- bb date 2014 
So in the interests of mn my daughters and I did a taste test. The chocolate looked in perfect condition, no bloom or anything. It had been stored at at stable room temperature.
It tasted odd, maybe I’m used to the new stuff now, it had a slight vomit undertone to it, it felt grainy on the mouth feel and didn’t melt in the mouth despite being at room temperature. Lots of things that have been levelled at the new version. It didn’t however feel ‘greasy’ as the new stuff does.
The DC didn’t discriminate and ate it, but they like chocolate coin chocolate too 
Compared to the new version of Cadbury’s, it wasn’t any better or worse, but my tastes have changed and I prefer dark now - preferably Lindt excellence 