External Hard Drive

Looking to purchase an external hard drive to attach to my Naim Uniti Star.  It will be used to rip cd's onto through the Uniti Star as well as hold hi res music downloads.  I've heard that Western Digital makes good external drives.  Are there much differences in the ones they make?  Mybook line?  Elements line?  Passbook?  Does the power make much of a difference (self powered vs usb powered?  Thinking of somewhere between 1 TB and 8 TB (likely 4 TB or 8 TB).  Thoughts?  Thanks!
I use Western Digital Red drives in my NAS and knock on wood it's been 4 years and not a failure. I have not tried one of their external drives so can't comment there but they make good products. And buy the 8TB I bought 4TBs myself and am almost out of space now.
In the imaging production environments where I used to work we relied on Seagate drives. I don't know that they're superior to Western Digital but those are the two well-regarded brands I'm familiar with. For an external storage drive where portability isn't an issue I would go with drives with their own internal power supply rather than USB.
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I can’t use a NAS right now because the Naim Star doesn’t allow ripping to a NAS (only to an attached hardrive.  May set up a NAS later after I have ripped my cd’s.