I thought brand wouldn’t matter either, but got unlucky with the Amazon special I purchased a couple years ago. When I actually needed it to help a stranded ICE car, it was dead. When I tried tried to charge it later that night, it literally smoked on me. After taking it apart before throwing it out (recycled), there were burn marks on the circuit board. Some component had given up the ghost.
Sprung for the unit from Schwaben (via ECS Tuning) and haven’t looked back, including helping another ICE car along with use as a USB battery bank.
