I've had many jump boxes over the last several decades, all of the lead-acid type, usually from Sears-O'Reilly-Autozone (and from now-defunct stores). My last one died two years ago, and I didn't feel the need to get another (all my vehicles have jumper cables), we have several cars at home to use, and my wife (both retired)and I seldom go anywhere together, so the other one is always available for a jumpstart (just a phone call away), until recently.
I ran my X5's battery down while experimenting using different OBD scan tools, apps, extension cables, bluetooth dongles, USB/OTG/FTDI/K-Line cable, and the X5 wouldn't start, though I had a 1.5 amp Battery Tender hooked up. After that, I moved my Schumacher XCS15 (2-10-15 amps) solid-state charger from my camping truck to the X5, so I could charge/maintain the battery while scanning, even away from home (I have a full-size, garage-type, old-school charger in my garage, too). But, if I ran the battery down away from home, where there was no 110vac to use, then how could I start my BMW?
So, after much research, I decided to try a lightweight lithium-ion jump box by Astro AI (I figured their stuff was OK, since my two favorite automotive YouTubers...South Main Auto & Pine Hollow Auto Diagnostics...use some of their tools or meters) from Amazon (my go-to for just about everything, with Rock Auto, and FCPEuro way behind). I like the Amazon return policy, too.
Originally, I had a GOOLOO jump box on my shopping list, but when the Astro AI popped-up, I took the chance on it. I put it in my automotive "go bag" (spare phone & battery pack, Foxwell NT510 Elite scan tool, extra MicroUSB, USB-C, & OBD2 cables, and now including the AstroAI), and take it with me whenever I leave home, just in case.
I haven't used it yet... perhaps I will before winter, but since I keep all my vehicles on charger/maintainers fulltime, I may never get the chance. I might leave the charger off the riding lawnmower battery for awhile (they never last long when unused over the winter, in my experience, and my main use for the last jumpbox I had, after quitting drag-racing, was to jumpstart the failing lawnmower battery). Who knows if it will be as good or long-lasting as the lead-acid jumpboxes I previously used (none were top-line units)?