I have shipped dozens of watches to the US including Rolexes using plain old registered mail but please describe as non working watch for repair as a deterrent.Fedex is a little troublesome as they will ask you questions about what the item is made of,how many % steel,gold where its made among other ridiculous questions.EMS is quite expensive actually as pos malaysia uses a third party carrier eg fedex planes so in actual fact,pos msia are agents.
If you ship a Rolex,make doubly sure you do not mention the name as Rolex watches are prohibited from entering the US and will be confiscated.