Every day I make a trip over to Homestead Survival to check out their free (at the time of posting) book selection and almost every time I visit I see a book concerning the perfect bug-out bag.
I downloaded the first few until I realized that the author is giving advice for his/her perfect Git Kit, not mine.
I quit downloading the damned things. If I including everything from every book I'd need a fucking moving van to haul my shit around. Not to say there's not some good ideas in the books, but I haven't added a single thing to my Git Kit. It still has a few meals and cooking gear, water filter, a change of clothes, shelter and sleeping gear, a first aid kit, and meds, firestarting stuff, 550 cord and other odds and ends. That's it.
Figure out what you need, how much you're going to need while remembering that in a worst case scenario you're going to put it on your back and carry it around.
Build it yourself for your needs.