[stevedusa]

Q2: Yes, they are different for both radios.

Q3: I am using Sprint and I am in China at the moment so let me share my experiences.
a: I believe in Sprint's case, it depends on where you are roaming into. When I arrived in China, I thought I was going onto an GSM network with Sprint's SIM card in there for roaming, but I was wrong. The phone actually went onto a CDMA network instead. I believe that Sprint has roaming agreement with the Chinese CDMA provider (China Unicom). I made a call back to the States and the voice quality is clear.

So long story short, by default the Global mode with Sprint's SIM in there, it will seek CDMA signal first, if it does not found anything then it'll try the GSM part, depending on what SIM you put in there.

b: I'd like to correct something here regarding the "SIM" for CDMA. It's called an "UIM" or "RIM" for CDMA networks. It looks identical to a GSM SIM card but believe it or not, United States, or in North America, the UIM/RIM is integrated into the phone, where the rest of the world such as China, the users can remove the UIM/RIM just like GSM-counter parts.

The answer? I had to test it tomorrow, but I have a feeling it will only accept GSM SIM, not CDMA UIM/RIMs.

c: That, you need to have your destination provider do it for you, AA Keys and such. Some providers does support modify or work with integrated (soldered onto) UIM/RIM for CDMA networks.

d: Of course you can, I have a China Telecom SIM card in my Sprint TP2 right now and I can make/receive phone calls on the SIM card's number, while my phone's CDMA part is still the State's number. Didn't try to use it without Sprint's SIM card in there though. I'll try it later.

Q5: No, not exactly. It depends on the destination's network infrastructure as well. See in China, they do offer European 3G bands AND services, however since the plan on the SIM card does NOT have a 3G plan, it keeps at EDGE (GSM) band. I think you need to have someone go to Europe with our GSM/CDMA combo TP2 and try it out.