Wait, 5.6.1.x, that's a PW1, right? That's roughly the EOL update, right?
I *may* had mine that up to date *and* patched at the time.
Unfortunately, I lent it to my brother, and that's all she wrote...
If I remember where the hell I could have backed that up, you may be in luck, but don't hold your breath, since I can't even check it actually ever was running that FW version...
EDIT: To answer the Kobo question, in short: don't put a Kobo next to a >= PW2 and play at browsing the UI or a book, that'll make you want to cry. The Kobo'll feel very much sluggier.
It's decent enough once you've forgotten how snappy a Kindle is, mind you. Hence the H2O being my daily-driver for the past two years. And cue ranting and raging each time I have to look at my PW2 again
.
EDITē: Yeah, no such luck on the backups, it's probably on the raid array currently sitting in pieces in the box of hard-drives in my basement...
Either that, or I gave up on margins even earlier than I remembered.