Purchased this a little over a year ago at the recommendation of a coworker (he has the next model up, the GB70). Bought two, one for my truck and one for my wifes Terrain. I also purchased the Caseling case for them, which is a perfect accessory - the jump pack, alligator clamp cables, and usb charging cables all fit inside a neat little package that fits under the back seat of my pickup.
Caseling Hard CASE fits Noco Genius Boost Plus GB40 1000 Amp 12V UltraSafe Lithium Jump Starter.
The jumper pack is virtually idiot proof; hook it up to a dead or weak battery, hit the key, and it takes off. You do need to be aware, the onboard safety circuits will not recognize a completely dead battery, but there is a safety override mode built in for just a situation like that - I ended up having to use that when I dug my 2002 Honda Accord out of a snowdrift before selling it. It had a 5+ year old battery in it at that point, and the previous winter I had needed to jump start it several times after it sat for a month without being driven -- this year, I had not driven it since the 4th of July. It was literally frozen to the ground where it sat, and the battery was so dead it wouldn't even start to turn on the dome light. Hooked this jumper up, and it turned over like it had a brand new battery. Here is where I really became impressed with the jumper pack - because the car was frozen to the ground, and had snow built up around the tires, I killed it (manual transmission, 4 cylinder) 10 times before I finally got it rocked out of the snowdrift. The battery was so shot it would no longer build a charge from the engine running, so I was starting it from completely dead every time. This little jumper pack never even hesitated, and when I finally got the car up onto clear pavement, it had only used 25% of it's charge. An hour or two plugged in back in the house, and it was back up to 100% and ready to go. That was 8 months ago, I checked it the other day, and it is still showing full charge. I'll probably plug it in sometime this week anyway, just to make sure it's absolutely ready for winter. We're buying my brother-in-law one for Christmas this year, and I recommend it to everyone I know. Excellent piece of equipment to have in your roadside tool kit.