Interesting stuff. I see people saying the Euro downgrade gets you 4.5.0-8E - I'm half tempted to try it as my sysnand is currently 4.5.0-0E (no eshop, browser won't run "until you update online"). 4.5.0-8E would presumably let me run Ninjhax, which could be handy as then I can update my emunand past 9.2 without losing the possibility of running ninjhax homebrew, and should also let me use Gateway's new browser exploit, which, uh, wouldn't have any immediately obvious advantages over the good ol' ds exploit, but hey, options are nice.
I'm guessing using the downgrade or sysnand-restoring features of GW would give the sysnand a new id, unlinking it from the emunand in the same way that formatting it would? Can anyone confirm?