4G service is just compensation for being stuck in Texas.
I use 4g for tethering to my laptops. I have a Sprint 4g device I use when I need to get out of the lab to stay sane. It is not that much faster than my ATT devices, but it gives you free unlimited bandwidth when in 4G.
ATT 4G should be much faster than Sprint.
NFC should be safe. It will only connect to one device at a time for financial transactions it will ask for a password on your device before it performs a transaction and it will have some kind of conformation code on the vending device to inform you that you are connected to the correct device. I am sure it will also use some form of public/private key encryption.
How many times to we need to keep saying this, Skunkwood North Dakota is not a major metro area.
I would not brag about one day. When you can get four days of heavy use per charge, please come back.
I think they are doing Chicago for the pizza. Chicago is also a great city to make money from gang violence. You can make a fortune sweeping up the brass after a big gun fight.