My first thought in the decision making process would be WHY are we bugging out?? Chemical spill or vapor release, major weather event, terrorism, civil insurection??? Any of the aforementioned would probably cause me to take two vehicles. Both are 4x4 and have reliable communications equipment, public safety and amateur equip. One of the vehicles is loaded 24/365 with about everything needed for an extended BO except water and means are readily available to handle that issue. Problem is, I'm probably only going as far as the Emergency Ops. Ctr. or directly to the event Command Post. Wife will BO to relatives out of state if the event warrants.