I presently drive a 2010 LS460L AWD. Prior to the LS460, I drove an 2006 Mercedes S430 4Matic. The AWD provides me with a vastly higher level of peace of mind in commuting (35 miles in each direction). Prior to these AWD vehicles, I drove for ten years a 1997 Mercedes S320 RWD. What a difference!
I would strongly urge you to consider the AWD vehicle.