Cellphone during vacation

I’m going to be traveling to Taiwan in a couple of weeks (just for a week vacation) and I was wondering about the cellphone situation. I read that you have to have a resident number (shenfenzhen) in order to buy a prepaid sim card, but then I also read somewhere that you can also get one at the airport (TPE) with your passport.

Anyone have details on this and also what the rates are like?

Or would it just be easier to get a phone card and use pay phones? We’re going as part of a tour so we’ll be staying in hotels like the Westin. I assume there are still lots of pay phones in Taiwan? (They’re almost extinct in the U.S.).

This will make a difference in which cellphone I bring - if I can get a sim card, I’ll bring my older, unlocked phone. But if it’s easier to just use the pay phone, I’ll just bring my regular (locked) phone in case of emergency (it has better battery life so I can use it as a clock/alarm).

I dont know if you can get a prepaid sim card at the airport. That’s true that you need to have shenfenzhen if you are going to buy the sim card outside the airport.
About the pay phones: I don’t think there are many of them. I assume you are going to make international calls, in that case pay phones suck. You end up paying 200NT for three-four minutes of conversation.
Why don’t you take laptop and use Skype? Since you will be staying in hotels anyway, you will have Internet access.
You can use Skype also on your cell, that would be cheaper than using regular phone.