I have a 3g gps device (gm36w) on my truck, a 2g device (gm02ew) on the sedan.
Truck is for when I am going to camp with friends or family, and rural area is best to have a strong signal device which is 3g because I analysed from the amazon market, the 3g probably is the latest signal format that these provides.
So for me, supporting signal is the top priority to pick the device, and incity area, 2g is pretty enough for my daily driving basis, less data cost, and it's cheap.
*Although LTE is popular, but too expensive for me, and for now, not so many gps support.
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