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Anyone who has an original RAZR and says a charge lasts them all day with 4G is on lying through their teeth...
I greatly dislike being called a liar, how about you find some other way to disagree with people, aside from calling them names.
Just because it doesn't work for you doesn't mean that it doesn't work for other people.
Given the great disparity between apps installed, widgets used, update frequenices, and signal strength in a given area, it's reasonable to assume there will be great differences in battery life.
On my OG Razr I can leave the phone on 4G all day and still have a charge at the end of the day - generally about 30% or so ('all day' for me is 6am to 9pm). My typical day is light usage, maybe 20 minutes of phone calls, 30 minutes of a podcast and an hour or so playing solitaire or something of the sort. I'm in a reasonably good, but not top signal, 4G area. Does 4G use more battery for me than WiFi or 3G only, absolutely. But it gets me through a day and that's my main concern.
If I know I'm going to go to weak 4G signal area for any length of time I'll switch over to 3G (or airplane mode). Having it hunt for a 4G signal, connect and disconnect, will kill the battery well before the day is over.