Just as an update on this. It failed on the Thursday, sorted out the RMA on the friday, by Mon 8th I had a new one. Can't fault the service centre's service.
Their customer support line however is shocking. On the thursday evening I emailed samsung support to start the RMA. They emailed back straight away to say "call this number to arrange a warranty replacement".
I phoned the number, gave the woman my reference and she said, and I quote verbatim, "I see you emailed us yesterday, you've had a response to that, so what's the problem?" in a tone that very much said "Why are you bothering me with this, someone's already dealt with you"
I pointed out that the response said to call, and she was then rude and obstinate throughout taking my details. Then hung up on me after saying "Right, our service centre will contact you on Monday, if they find you damaged it yourself, you will be charged for the replacement". I didn't even get a chance to respond to that before she hung up.
I was very British and polite the entire time, I really don't know what I had done to get that kind of response.
Luckily the woman from the service centre was unfailingly polite and helpful.