Last night after 2hours 14 mins it was on 49%. At that point I went to bed.
SO I estimate around 4 1/2 to 5 hours for full format.
I didn't think mine took that long, maybe 3 hours through Vista's Disk Management. Like people have said already, it always seems like a good idea to do a full format on a new drive, you can always be doing something else while it's formatting anyways.
As for the failures, it would be a different batch going to the USA so it could just be an issue with an early production run. I've not seen too many issues on UK forums either. Regardless I always run a full test using the manufacturer’s dos tester first and would never put anything I wasn't willing to lose on a brand new drive.
I expect most people are using them as storage drives and filling them with downloads, so it shouldn't be too much of an issue.

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