My immediate family --and I must include myself in this-- would all have to plead guilty if charged with being procrastinators.
I don't have a BOB per se, but when it comes to "bang stuff", we're ready to go. The main gun will be a Winchester 1300 Defender (18", cylinder bore, full length mag), which is already loaded, as is the buttsock, as is the side saddle, as is the bandoleer style sling. I'd have to count, but I think that's about 30 rounds of 12 gauge at the ready.
We'd automatically have what I'm already wearing (24 rounds of .45 ACP), and a quick sweep of the shelf into a handy range bag would add handguns in .22, .38, and 9x18, all in handy paddle holsters, and another sweep of the arm would dump several hundred rounds of ammo into the bag as well.
And of course I would grab as many rifles as we could carry easily, and an ammo can full of bandoleers, which have loaded chargers ("stripper clips" for those heathens who don't speak Enfield.

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Total time to load all the "bang stuff" into a vehicle would be about three minutes.
Total time to throw toiletries and changes of clothing into a duffel and load all four of us into the van, maybe 20 minutes. That includes dog food and bowls, and (at current count) four adult dogs and four puppies. Love the cats too, but they live outside and would fare just fine without us, so we'll dump a bag of Purina on the porch and look for the cats when we get back.
We have multiple gallons of drinking water ready to go, plus a generator and six NATO 5 gallon cans of STA-BIL'd gasoline. Travel trailer is ready to hook up and ready to live in at any minute, although we'd have to transfer some groceries from the house. Three multi-band radios (including SW) and batteries are always ready, as are flashlights (plus spare batteries).
Our bug-out time would range from under 10 minutes for drastic "get out, now!" situations, to a couple of hours if we were facing a long term evacuation with some advance notice.
For those of you facing bug-out from major urban areas, I would like to stress having the DeLorme "Atlas and Gazetteer" for the state where you live, plus adjoining states where you might have to travel. Keep them in your vehicles at all times. Know how to read the maps. While the rest of the world is parked on the northbound interstates, a good map could have you plugging happily along on secondary roads.
But!... know where the choke points are!
If we were to get more serious about it, one thing I would add to our plan would be a decent dual-sport motorcycle, for route recon. FRS/GMRS radios for communication if cell phones aren't working, and the motorcycle scout can guide the family bus around the worst of it.
Okay, so I just want a good thumper motorsickle. But any excuse in a storm, eh?
Kevin