Which 8TB Drive to use in an external enclosure for backup?

The user has a nice CRU external enclosure that supports 8TB drives, and connects to their iMac with FireWire or USB.
They are using Retrospect software to back up.

There is a Seagate Archive 8TB HDD  for $240 on Amazon
https://www.amazon.com/Seagate-Archive-6GBps-128MB-ST8000AS0002/dp/B00XS423SC/ref=sr_1_1?ie=UTF8&qid=1485837363&sr=8-1&keywords=Seagate+Archive+HDD+8TB+SATA+6GBps+128MB+Cache+SATA+Hard+Drive+%28ST8000AS0002%29

The next model up seems to be a Seagate 8TB BarraCuda Pro SATA 6Gb/s 256MB Cache 3.5-Inch Internal Hard Drive (ST8000DM005)
https://www.amazon.com/Seagate-BarraCuda-3-5-Inch-Internal-ST8000DM005/dp/B01LOOJBNW/ref=sr_1_1?ie=UTF8&qid=1485837473&sr=8-1&keywords=Seagate+8TB+BarraCuda+Pro+SATA+6Gb%2Fs+256MB+Cache+3.5-Inch+Internal+Hard+Drive+%28ST8000DM005%29

The reliability of their backup is important.  They will take this drive and store it off-site for some time.

Is the BarraCuda Pro more reliable?

Thanks.