I use pure2 6.3 on my 4k+, the one I loaded was "osmio4kplus-PurE2-6.3-20191215_usb"
I don't recall any issues loading it. Their may be a newer version if you look?
Don't know what you mean by any differences?
They are all different one way or another, but also pretty much the same?
It has Kodilite on it, which I like.....
GOOD LUCK..!!!!
Al
P.S.
I'm pretty sure I didn't use the thumb drive to load it.
I ftp'd to the downloaded_images folder, and loaded it that way.