It is clear that the 'design fault' is not with the computer itself, it is the packaging. Considering the size and weight of a 27" iMac, it does need to be suspended in a shock-proof box. I had exactly the same thing happen with a 40" Sony Bravia tele, arrived with a cracked screen. Although the carton contained the television, it was never going to protect it from a drop or face on impact in the back of a lorry. Expanded polystyrene has virtually no shock absorbing qualities and transmits the energy of any impact to the contents very efficiently. The iMac 27" packaging is not fit for purpose and Apple are finding out the hard way! It's a lovely machine in the flesh.