I have the Razr Maxx and my wife has the Bionic. Both are great devices. The Bionic though has the better radio and picks up and keeps the 4G signal WAY better than the Razr. Not only my razr but her friends that have razr drop 4G in our area alot and her Bionic is STELLAR!! Extended battery on the Bionic will give you over a day of use and the regular battery a day or so.
If I was choosing between the Bionic and the Razr (OG), I would take the bionic in a heartbeat
Both are slated for ICS so OS is a mute point