Once you have "accepted" the products (by keeping it for a reasonable amount of time), you are only entitled to a repair or replacement (as decided by the retailer). You are only entitled to a refund when:
- You reject the goods within a reasonable amount of time
- It is impossible to repair or replace (for the retailer)
- Its too costly to repair or replace (for the retailer)
- Or the repair/replacement cannot be done within a reasonable time, or without causing significant inconvenience.
By the Sales of goods act, under these circumstances you aren't entitled to a refund, you might be able to request gift vouchers (store credit), in which you could purchase something else from the catalog but they don't have to offer this to you.
Feel free to check out the SOGA factsheets from dti/ts
Sale of Goods Act Quick Facts - DTI Trading Standards Central - Trading Standards and Consumer Protection information for the UK Trading Standards Central - Trading Standards and Consumer Protection information for the UK