I'm a big fan of these devices. I had
this one for 4+ years. No issues and jumped my truck and other peoples' vehicles multiple times. Recently my alternator died and I had to jump my truck almost 10 times, all on one charge, and it worked perfectly. So I wasn't terribly disappointed when I pulled the booster out a couple of weeks later and found it had given its life in the line of duty. Battery had swelled so much it forced the case apart.
Just
bought a new one and like it so far though there's been no occasion to test it.