re the Jump Start jumper batteries - Dargo, you got the cheapskate one. (400/900 amp, 17 AH).
I got the big yellow one, the one where the back of the case is extended for an oversize battery inside. I think it's 600/1200 amp, 24 AH. It works fine. I don't see them online now so maybe that was a closeout.
I am also accumulating DSL modem/wireless router gear that is all 12 volts so I can have wireless internet to our laptops during a power outage, all powered from that battery. Even before locating the last of these components, I can run my existing gear through an inverter powered from the battery. And if the power should be out for days, I could recharge the laptops from the inverter, then recharge the jump battery from running my car.
It's good for more than just jumping cars, it's a universal emergency power supply, for home or even car-camping.