Cellular

This is depending what you expect to do with your phone. Do you want to only talk with it, do you want to use SMS, MMS (multimedia message service), camera, mobile internet, custom ringtones, mp3 player. Nowadays, you can have all that.

If you ask me, I'll tell you that Motorola phones are usually quad band and aren't really expensive. Take example on the RAZR. It has bluetooth, it's quadband, a camera, SMS, MMS, mobile internet. If you can find an unlocked one on ebay I think you can get it for less than 150$. When you get to HK, just go to any operator that is a GSM network (not CDMA), and only buy the SIM card with either a monthly plan or prepaid plan.

So when you get out of HK, you can always do the same thing with your local GSM operator.

CDMA phones only work for the carriers that sell them. It is very hard to make let's say, a Verizon phone on another CDMA network without being in roaming mode. CDMA does not work as GSM works so it's harder to switch operators withtout some expert tweaking.

But any unlocked GSM network(900/1800 MHZ preferably) phone. That or any phone supporting 3G (cause the asian market is way more advanced than everywhere else on the planet. They're working on 4G for god's sake!)

Jam it back in, in the dark.