it is my understanding that the 850 band is used by some gsm providers in the United States, the other bands are used in Europe amd Asia
I'm starting to travel for work all over the world, so I wanted to get a mobile phone that can be used anywhere. Given this, I've narrowed the phones I want down to either a tri-band GSM (Sony Ericsson z600) or a quad-band GSM (Motorola v600 or v400).
The confusion I'm having is trying to determine the difference between the tri-band and quad-band. A tri-band has a frequency of 1900, 1800, and 900 Mhz. A quad-band is 1900, 1800, 900, and 850.
One sales associate has told me that the triband will work any where in the world and that the quadband's extra frequency coverage is just to get a more clearer reception. Another sales associate told me that I would need the quad-band, because it offers the most extensive GSM world coverage. When I questioned the guy where does the quad-band cover that a tri-band doesn't, he couldn't say. (Sounds like to me he was just quoting a sales brochure!)
Can anyone clear up the confusion?

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