Okay, so I've upgraded two 8125's now to the latest ROM's. This one went pretty flawlessly, unlike the first one (my fault).
Anyway, there's a reason they tell you at least 50%:
Anyway, overall, it's a pretty straightforward setup. If you've ever done ROM upgrades before, there's always a cause for minor concern. But, I'm so bullheaded, I walk in fearless. Thankfully nothing bad has happened yet.
Anyway, these screens are in the order they happened in, and assuming everything goes okay, there shouldn't be any problems.
And finally, some pictures of the phone during and after the upgrade:
I should note that in the phone pictures, you'll see the progress bar going to red. Normally it's green. In both upgrades I've performed, it's done that at the 80% and 95% marks. It hasn't failed, I'm assuming it's just finalizing something or whatever. Regardless, in both cases, the upgrades have turned out fine.
Not sure if this will be useful to anyone, but here it is anyway.
Cheers!