It's not too bad. I prefer the milk one though. I'd love Cadburys to do a slightly fatter Flake bar with fillings such as mint fondant or turkish delight or even something really special like pineapple cream.
In the 1950s (I don't remember these, I saw them in a Robert Opie book) Cadburys did little CDM bars with strawberry cream filling, pineapple cream filling and tangerine cream filling. I am sure they'd be popular if they considered something similar today.