Without naming names;

I bought a seat post in January of this year, a couple of weeks back it was creaking (I thought it was the saddle) anyway to cut along story short the clamp head has now rotated in the post, so it's dead.

I've returned the post to the retailer, it's faulty and it's within 6 months of purchase, I want a refund as they don't have the post in stock (I don't want another one anyway, not if they break that easily) and it can't be repaired, they are offering me vouchers and I want a cash refund, they have refused.

Where do I stand?

http://www.consumerdirect.gov.uk/after_you_buy/know-your-rights/SGAknowyourrights/