the best shipping option for most of my watches is the Global Priority flatrate cardboard envelope which costs 11$ worldwide and can contain 4 pounds of goods.
it can be quite thick with a wrapped item inside and I've received some small watch boxes this way without a problem. the only necessity is to secure the seems with transparent tape.
Global Priority boxes and other mailers are more expensive and have a variable cost based on weight - usually 25-35$
check more mailers at:
http://shop.usps.com/webapp/wcs/stores/ ... ryId=13356
Surface (economy) mail is no longer available since the big changes at USPS in May 2007.
First-class is the new name for Airmail and is very good for small cheap items and vary from 3.5$ to 8$.
Registered (signed-for) option is currently 10.15$ and can be added to First-Class and Priority non-flatrate. Insurance is available and is tracked online on a limited basis - you only get the information that it was sent, left the US, and was delivered to your country on day X.
Express Mail (USPS courier) is very expensive but has full online tracking and has insurance. others such as DHL or FedEx work the same way. most of such items will be stopped at customs due to the real value stated on the package.
I've lost some 5 watches in the last 5 years but I no longer use registered or expensive shipping.
Calculate this average example yourself:
100 watches per year x 11$ flatrate = 1100$
let's assume 2 get lost equal to 300$
total: 1400$
safer and more expensive alternative:
100 watches per year x 30$ average priority = 3000$
total: 3000$
so even if I loose one or two watches, I'm still saving plenty of money.
when I ask the seller to ship a "slightly" more expensive watch I use priority insured and registered or first-class registered.
PS. additionally you also save heaps of money on customs fees :)