The only time I would get burned is via buyers remorse - and how would the buyer prove their false claim that the amplifier isn't working?Peter, while I'm not suggesting that it is likely to be a significant possibility in this particular situation, you should be aware that if you Google "paypal empty box scam" (without the quotes), you will find many reports of scams, generally involving eBay sales transacted via Paypal, in which either the buyer claims to have received an empty or weighted box, or claims that the item is significantly not as described and then returns an empty or weighted box.
See for instance the post dated Jan. 2, 2011 at 2:53 p.m. in this thread, in which a seller on eBay lost his case with Paypal against such a scammer, despite having been able to present extraordinarily good documentation and photographic evidence in support of his case.
Just something to keep in mind.
Regards,
-- Al