Returning a 1 day old item (opened) to a shop, rights?

[bledd]

My mate bought me mario kart for the wii yesterday, and he bought me a 2nd steering wheel (non nintendo) it's far poorer than the nintendo one

I've got the receipt for it, for £6.99

Am I able to return it for a full refund as it's less than 7 days since it was purchased?

I opened it (you can't tell it's inferior until the packaging is removed)

Box is still in good condidtion, as is the product.

Do they have to refund me?

 

[bledd]

Damn

I thought you could return anything (besides food) within 7 days of purchase, no questions asked

 

[bledd]

Ok

I'll tell them it's crap (the nintendo one has a hole in the side, so the infra-red pointer can 'get through' it, the 3rd party one is sealed all over, which means you've got to take it out to use the pointer, so it's a pain in the backside