I said early in the thread that I bought a Noco GBX155 - which i think is their top of the line a year or so to replace my now 6 year old JNC770. Well I finally figured out that you need to keep the NOCO Charged at all times. I finally started leaving it plugged into the lighter socket in the back seat of my pickup. The NOCO has some great features and some awful features as far as I'm concerned.
NOCO GBX155: Pros - It kicks really hard when it works. It is small and compact compared to a traditional jump box. Cons - It will only start 1-2 vehicles on a charge, then it needs recharging, It won't start a vehicle with a completely dead battery - it must sense some voltage. It has a feature that says always on, but I can't get it to work. Cables are pretty short. Only charges with USB C. Had to buy a USB C fast charger for $75 to get it fully charged. Expensive
JNC 770: Pros - Great cables - nice length, heavy gauge, Will start almost any vehicle, including a diesel truck when well charged. Will start a vehicle with no battery present. I've used it to run a trolling motor on a small boat. Will jump several vehicles on a charge. I only charge it periodically. 110V charging system built in - just plug it in to any extension cord. Cons: JNC 770 has unique cable clamps - they work, but some don't like them. Bulky and a little heavy.
If I could only have one, it would be the JNC 770 - or JNC660, which has the same capacity. That said, I often pull out the GBX155 first because it's so compact and lightweight. Unfortunately many times I have to go get the JNC 770 when the NOCO doesn't work.