Verizon has faster 3G. AT&T has HSPA+ which is like 3.5G. The AT&T 4S seems faster because it's connected to the HSPA+ network. Verizon has the fastest 3G network out of all of them.
The Verizon model is better because Verizon is a better carrier (for one they don't false advertise their networks).
That iPhone unlocking is only AFTER your contract is over.
Calling and Surfing the Web at the same time is kinda stupid if you ask me, anyways.
So being on a phone call and then wanting to look something while on the call with the person and responding to them without having to call them back is stupid? I guess so lol
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when i got my first very first phone which was the iPhone 2G service was good then it got worse overtime.
Then maybe you should have switched lol. For me At&t service is perfect I don't have issues with dropped calls.