All that you say is absolutely correct about the bicycle. The dual-purpose touring bike can be quite usable off-road and not too big a penalty on-road - especially in a heavily laden BOB type scenario. Also one of the aftermarket add-on gasolene engines may make the first day or so - the really important one in an evac situation - much more pleasant. For a little effort with a wrench these can be added or taken off. The cost in weight of the smallest was 14# which is considerable if you have to pedal but meaningless if it is hauling you and your BOB. If you run out of gas and can't forsee getting more, it is easy to stop for 10 min and dump the 14 #. OTOH if you have a reasonable chance of resupply then it might be worth hauling the extra 14# along as you pedal the rest of the way to the gas-station. Since you will be rested from not having to work for the first 200 miles as the gasolene engine pulled you along you may be able to pedal the extra 14# of engine up over that last hill looking for a gas station or abondoned vehicle with a gallon of gas still in the tank. These engines are claiming 80 - 100 MPG and come with 2 -2.5 gallon gas tanks. Also, when you reach your evac shelter the small gasolene work-horse can be adapted to power generators, mini-sawmills, compressors, pumps and other handy devices that you might have there that won't be getting power from the grid.