We have two, both Suaoki brand (which may not exist anymore) from Amazon. They are 7 and 5 years old. and still keep their charge like brand new. I have never had an issue with them jumping my car, or my riding mower, or other peoples car. I have used them much more often to help out others than to jump our own cars. The only times I have to use them on our cars were a few times with very old, dying batteries that I did not proactively replace.
The battery jumping is much easier than cables between 2 cars , in my view. No need to worry about the order, just connect them to the battery terminals and turn on the jumper, then disconnect. If one can open the hood, one can use these easily.
The USB ports and LED lights they have are a nice bonus, for use as a portable charger and flashlight. I usually recharge them 2-3 times a year, normally before a long road trip.