Can't say I've ever bought a reconditioned one but if doing so I'd avoid PC World like the plague.
For under £500 though, I'd seriously suggest a new one from one of the major 'resellers' E.g. Insight
Deals at Insight UK Most of the big manufacturers make a batch of a particular model and then three months later they change the spec before making another batch. Any of the first batch they haven't sold get passed to resellers who price them to sell quickly.
At the suggestion of the tech guys at Toshiba that's exactly what I did when looking for a new laptop on a budget. £350 for a really nice machine with Toshiba's money back warranty thrown in for good measure.
Good service from Insight too - minimal fuss when ordering and it arrived the next day as promised. AND, I see that some of their Tosh laptops are still available with XP downgrade
Let us know which route you go and how you get on please?
CS