Without going too far off the deep end on this, I do have some deversity of devices at my disposal. Here's what I find so far. (Mind you. This is in the charlotte, nc metro area and within 20 miles eitherway at this point).
T-Mobile Devices ( Nexus One and MT3G)
Neither seems to hold 3g for any period of time. The calls are solid and coverage for the basic system ie. phone works great. Data on the other hand is spotty on both devices switching between edge and 3g (and of course in some areas just looking at you a bit funny going... Really? you expect me to work here..
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Verizon (Moto Droid)
Unless you get to the outskirts of a populated area, the device shines. Although I have poor signal at the office, at home with all devices I have 5 bars at all times.
It's kinda hard to pin down the T-mobile thing as both phones I have are HTC. Maybe I'll try getting ahold of a blackberry from someone at the office and see what if anything that does compared.
As per the phone itself, I've been very satisfied. Mind you, I generally use wifi at all times except the drive home and well, don't do much usage of the data side while driving
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