for sure, i get 1mbps on full 3g, and 6-8 mbps on 1 bar LTEYes, there is a toggle under Settings>General>Cellular>Toggle Enable LTE.
Supposedly though, battery life on 4G is equivalent to 3G. At least in my area, 2 bars of 4G coverage is ridiculously faster than full 3G. Maybe battery life would be better on 3G though if it is constantly searching for 4G?
(btw, I know the pic says ATT. I found it online. It is the same on Verizon though.