Hmm - MTH Engines ship in a hard foam enclosure, surrounding by thin cardboard, and then in a card board box, Have to assume their shipping packages are designed to handle a 4 foot drop. ???
That is a puzzle, why they don't arrive damaged. There is nothing really loose in them that would move on impact and break off, and they are quite tight in their cocoon, maybe that is the issue, they are inherently safe. I did ship a large item in its original cocoon, and original box, outwardly it was a solid aluminum box, but within were many things installed on standoffs. FedEx dropped it, and inside the unit, every single component on a plastic or ceramic standoff was snapped off. FedEx initially said it was not packed properly, but my pics showing an undamaged box, and the receiving ends pics of the deeply flattened corner, got my 600 bucks back, but they only refunded half of the cost of shipping. Some of the problems are generated by crooked folks that send damaged goods and then claim the shipper broke them, I learned this when sending a large item, and the pack and ship place notified me that if they pack and ship it, if anything goes wrong, I will immediately receive a refund, and they deal with the shipper. There is some kind of inherent understanding that these pack and ship places have with commercial shippers that they know what they are doing, but to be honest, some of the worst packing jobs I have seen have come from such places.