I've seen some how-tos on drive shucking. Recently I ran the HDD Guru Low Level format routine
on just a 2Tb Hitachi (refurb purchase) and it ran for a long time (had to shut it down since the HD was too hot and I returned it.)

But it leaves the question: How long would a HDD Guru Low Level routine on a 10-12Tb shucked HD take? Is there an extreme advantage to using the paid version of HDDLLF? Or alternatively, if using the Western Digital tools for the old Hitachi (which from previous Q's was recommended), how long would that take on one of those very large capacity HDs?

These days the only point to a "Low Level Format" is to make sure the drive can write all LBAs and its initialized to a constant value. Back in the days of MFM/RLL drives a real low level format was how you marked all the drive's defects and added all the sector markers, no drive made in the last 30 years allows the user that kind of low level access through standard commands. Its usually a safe bet that modern healthy hard drives can write 500-1000GB per hour so for a 12TB drive you are looking at up to a full day to perform the low level format.

Thanks for answering.

Ok, so the Quick Wipe shown in the options to get rid of MBR and boot defects is all that is
needed or preferred?

You can get an idea of the time required for a full zero-fill (aka "low level format") by examining the reported time for a security erase in the Identify Device info block.

Otherwise, run a read benchmark in HD Tune and record the average transfer rate. Then calculate the overall time based on this figure.

For example …

(12 TB) / (150 MB / second) = 22.2 hours

https://www.google.com/search?q=12+TB+/+(150+MB+per+second)+in+hours

I would suggest that MHDD (DOS) and HDDScan (Windows) are better tools for checking your drives.

_________________
A backup a day keeps DR away.

I will follow up on these these suggestions.

I recall MHDD from years ago. At that time I never got a good working knowledge of it or there were scary warnings about 'don't do this at home' words to that effect.

The two other scanning tools are new to me so I'll see what they offer.