I've only ever used Kiwix ... it's the easiest and most easily installable on different devices.
I've downloaded the entire database about six times now over the past few years. I keep a duplicated copy everywhere ... laptop, tablet, storage drive, portable drive, smartphone ... in multiple places at home / cottage / relatives place
My latest download will only be to have an updated copy as my last one is about a year old.
I don't like doomsday prepping and I don't really prepare for anything. I've been self sufficient all my life and if the world ends, I'll be able to make do on my own, I always have. But when it comes to knowledge and information, keeping a copy of Wikipedia is no-brainer for me.
I'm not the prepper person either, but I like to be self-sufficient and not be overly reliant on modern technology. My primary use case has been during travels.