When I have 45s sent to me registered from the UK to Sweden I always ask the sender NOT to send it by "airsure". As you wrote, "airsure" doesn't require a signature when delivered, the package is simply slipped through the mailbox just like an ordinary non-registered package. I fail to see how the seller can prove that the package has been delivered when using "airsure". They might be compensated by Royal Mail if the package goes amiss, I don't know, but from a buyers perspective who wants to recieve the 45 rather than getting a refund it's a crap piece of service and not worth paying extra for.