Which brands? if you have only ever eaten Cadburys going to a 70+% cocoa might be an unusual taste, and in America big brand chocolate is even more adulterated than it is in the UK
Comparison of th ingredients of Cadury's Dairy Milk in the UK vs US [0]:
> According to a 2007 report in The New York Times, a British bar contained (in order) of milk, sugar, cocoa mass, cocoa butter, vegetable fat and emulsifiers, whilst the American version manufactured by Hershey started its ingredients list with sugar. It also listed lactose, emulsifier soy lecithin, and “natural and artificial flavorings".
Cadbury's is typically the cheapest brand of chocolate in the UK. The UK got an exception from EU law to create a new type of 'family milk chocolate' that only contains 20% cocoa solids instead of 25% as is required in the rest of the EU to call something milk chocolate [1]
Sorry I only remember Cadbury's but there were other brands. As for taste in the UK and America, for the American market Lindt chose to adulterate their standard Excellence recipes to adjust to local preferences; consequently some of their dark chocolates sold in the US became inedible monstrosities.
