Sounds like this is the same as Brewdog Hardcore IPA. Their Punk IPA is less strong but still wonderfully hoppy.
Back to the Tesco Ginger Beer - it's not as sweet as Crabbie's or Franks, very refreshing and definitely ginger. Bit like champagne!!!
And finally - the best draft ginger beer I ever had was at a brewpub in the Glasgow suburbs called the Clockwork Beer Factory - this was a bit cloudy and over 5%.