you definely cant take the game back once open in England

sucks
I believe, in Belgium it is also NOT possibly to bring a game back and have your money back!
Maybe in Belgium you can change it for another game of the same prize or they give you a purchase worth of the game you bring back ... but I think it isn't possible in Belgium.
Maybe there're gameshops who give you "the chance" to
try out first the game you will buy ..?
But also I think something is only possible with consolegames and NOT with pc-games!
(but I'm not 100 % sure)