OMG. You guys are all speaking the truth. There is really no "best" for everyone. You have to experiment. Get a device, go to places that you spend most of your time. If not satisfied, return the device and terminate the service within 14 days without hesitation. Don't let them sweet talk you into deals. Remember, if you can't use the device/service, it does not matter how cheap and what bonus they give. Don't worry, if you decide to joint later, they will always let you back in.

Where I live, I only get Sprint and Verizon signal (consistantly). If I have to use BB, Verizon becomes my only choice, thus the best for me, plus I don't travel international. Pricing actually comes in second importance. If you can't use the device/service, it does not matter how cheap it is. But I am sure my neighbor across from me, who gets pretty much any carrier's signal in good quality, will have a different opinion.