My Book vs. Elements Desktop 8TB

Whats the difference in the hard drives used by these products?
The specifications look identical.

Which one is more reliable?
Any difference in their warranties?

This will be attached to my NAS for backing up my NAS data. Am I better off buying a WD Red and putting it in my own USB3 enclosure?

Thanks.
Aloke

WD Element Desktop and My Book, both are desktop hard drives and have higher data transfer speed with USB 3.0.
Difference is that WD Element is a basic plug n play external drive without any hardware encryption and software or tool. While My Book comes with backup software, hardware encryption feature and password protection tool.

Which internal drives do they use?

The warranties are different. So the drives used must be different.

Aloke

I am trying to determine which of the 2 external drives (6TB size) would be better to attach to my PR4100. My plan is to use the PR4100 back-up feature. Any help would be greatly appreciated.