I have the Noco GB70 2000 amp unit. I know several others with them. Including a buddy who uses the GB150 4000 amp unit at his repair shop. Seem to be pretty solid.
My issue is that I am afraid to leave it in the car with fear that in freezing temps it will burst the battery in it. So it sits at the house most of the time. Where is probably where I'll need it least. haha
That's the only thing that's stopped me from buying one lol. I think I might pick up the 1500 amp unit to leave in my desk drawer at work. 9/10 times I've needed a jump pack has been in my work parking lot.