Bests & Worsts Reviews from Amazon

This is for the supercap2 device. The product looks good, feels solid, and is relatively small (see picture taken against my 15" macbook pro). The interface is of minimalist style - Instead of using indicator leds to show the status, everything is now on the LCD on the top edge of the device. The display is tiny but does provide very useful and clear information. I tested charging with my laptop, with the car cigarette lighter, and with a car battery. They all worked fine and the LCD display shows the progress along the way. Charing with 5v USB is slow. I think it gets from 70% to 100% in 20 minutes or so. Charging a completely depleted unit takes about 1.5 hours. When charging, it shows the input voltage (for example my macbook outputs around 5v) and the percentage of charging. Once charging is done, the status will switch to "jumpstart" mode. There it will show the jumpstart voltage available and capacity percentage. You will press one button to start the discharge, which initiates a 10 seconds countdown to get you ready to go back in the car and turn on the ignition. It is as simple as that. I did have to get an exchange via Amazon as the first unit delivered to me was a DOA. Glad amazon made the exchange process so simple. I also contacted Autowit support trying to understand what the issue was with my first device. Support is very responsive and helpful as well. Update August 2021: I have had this for about a year now and never got a chance to really use it besides the initial tests. It was basically sitting on my bookshelf in the house for the entire time. Today I had to go and rescue a buddy. To my dismay, this device failed to work. It charged up to about 75% and automatically switched over to jumpstart mode. 75% is not enough juice to jumpstart a car unfortunately. No matter how I tried to charge it (usb/cigarette port/car battery), it is stuck in jumpstart mode and refused to charge up. I am trying to contact support now. Will update as this support case progresses. In the meantime, I am dropping its rating to two stars for poor reliability.