I think if you can get solid polystyrene in there, it's better than peanuts. Also, I don't know how the A1000 case opens or whatever, but consider putting cable ties round it or something, stress during delivery mangled a PC I bought on eBay once, and a simple cable tie round the machine would have prevented it.
Also, make sure you mark the box 'THIS SIDE UP'. Lots of things get shipped upside down and absolutely slaughtered in carriage because of that too.
