As many of you know, there isn't a real easy way to turn off 4G on the RAZR. This alarmed me because my office gets horrible reception and my RAZR used to get extremely hot at work and last me about 5-6 hours.
After upgrading to ICS I thought I would be forced to turn off mobile data unless I was actually using it. But, I figured I'd give it a try with 4G enabled first to see what impact ICS would have.
I am NOT disappointed. All day today my phone had an average of -105dbm yet my 4G never cut out (with gingerbread I'd lose my internet connection whenever my phone would get close to -95dbm). I took it off the charger at 7:30 AM and by 5:00 PM I still had 45% battery. With gingerbread my kernel would show the higest percentage used at 60% battery usage, yet with ICS the kernel only showed 24%.
I should note that I did have a smart action enabled that turned off background sync when the screen was off, but I also had this with gingerbread.
So, I have to say that any radio improvements made with ICS really did the trick for me. In fact, the only downside I've seen in regards to internet connection is that it seems to abandon my wifi connection and switch to 4G more often than it used to.
Edit: I should call out that I'm on the regular RAZR.