No Need for 4G... by the time they got it up and running it will be such a headache to even get into the subway, u will probably stick to cycling. You ask why!? Redicuously overzealous security meassures:http://www.thenanfang.com/blog/longer-delays-as-beijing-metro-security-check-dramatically-increased/
I was on the subway over the weekend and didn't experience any additional security measures. I would wager a guess that Tiantongyuan is like that every day, because it's always overpacked at the first station. Too many people living far north of the city just to afford their rent.
Again, poor research by bloggers. The increased security measures are only at 4 stations, none that are in the typical expat circles
Beijingcream has a much more balanced report on it http://beijingcream.com/2014/05/you-should-probably-avoid-these-beijing-subway-stations/