You pays your money and takes your choice.
I like to "image, image, image"; but that's just the OS, that's one reason I want it "lean and mean".
I do have external backups for my sample drive and for my projects.
2 drives will work, 1 for OS and 1 for projects.But that's bare a$$ minimum IMHO.
I have 5 drives on my office system, at least that in the studio...
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