I don't start worrying about shipments from Europe to the US for about 3-4 weeks. 10 days is pretty typical, but anything that might get stuck in customs, particularly around the winter holidays, could get waylayed for another couple of weeks. Some international postal systems have tracking that dovetails between systems. For instance, you can send Global Priority with tracking to Canada or Germany and then track it on the other side, and I would assume there are reciprocal arrangements in the reverse direction for systems that are compatible in that way.
National postal systems are very commonly used for high-end goods, like diamonds, because the insurance mechanisms are easy to use, and it is possible to send registered international packages with stamps on all the seals to make it easier to detect tampering. Good enough for diamonds, good enough for cameras, I'd say.
That said, for countries where there is good reason to have some doubts about the postal system for particularly costly goods, I've used DHL or FedEx just to avoid the three weeks of limbo not knowing if it's going to make it. If the value of the item is less than a few thousand dollars, it probably isn't worth paying for international express courier service.