I live in Asheville NC, which was just hit hard by Hurricane Helene. I was without power for four days and tried to rely on my Jackery as part of my emergency preparedness. It held a charge since the last time I used it (about three months ago) and I was able to charge my devices via USB, but the AC output wouldn't work. I contacted customer support, who gave me the runaround. I followed their troubleshooting steps, took a video of the problem (and then rode my bicycle to a satellite hotspot to upload it, since I didn't have any internet during the disaster), and then Jackery's customer support disappeared. I've received more help from FEMA. And they didn't waste my time.
I enjoyed my Jackery while the stakes were low, but if you're considering buying one as an emergency prep, I would look elsewhere. When all the dust settles, I'll be looking at Anker.