It depends on how you ship it.
They have an overnight service but really its almost a 2day service, then the 3-5day mailing which is usually 3 or mid-day on the 4th day, and then longer like 5-10 10-20 days mail by ship or something.
So it depends on the size and how fast you want to mail it and the cost. More expensive fast mailing cheaper slower.
Normally things I have sent from the US to Taiwan reached me within a week.
But if you notice a typhoon is approaching the island, expect to add a few days to the delivery. I made this mistake once and ended up waiting a month for an next day package.