Surely a defect like that would have been covered under UK/EU warranty anyway though since there's no accidental damage/user-caused damage to my macbook.
Still in two minds about it, but leaning towards not getting AC. Some have said that Apple gives AC free to higher education students but i've already bought the laptop and it costs about £150 to buy on it's own (from HE store, else it is £200). I'm thinking that the £150 would be better saved for maybe 3/4 years time when upgrading.