Though the razr has the same battery life as the bionic I would opt for the Maxx because it is the same size as the bionic but twice the battery for the reasons you said too. My wife has low usage and is on wifi most if the time so it is never an issue for her with the razr. I don't see upgrading again with Verizon an now with their crazy fees. They are more expensive and lte has become a joke IMO.
Only a world phone would be a reason at this point. It has dual core and dual cameras. Does everything I need.
Razr Maxx HD BL Unlocked, Rooted Bionic GSM enabled, Stock Razr, Eris 2.3.5 GSB, Inc2 Froyo, 1.2Ghz Droid X Koush recovery, Rooted Fascinate, DIs, Ally, Charge.