I don’t mean to disparage Vivian too much. In many ways, he forms a basis of Devon and Cornwall genealogy. I definitely use him as a source and I actually would, in general, feel OK about adding wikitree profiles from his works.
However, just know that his work is much more than just a Visitation. He used every conceivable source he could find to build these pedigrees – from good ones like wills, feet of fines etc., too bad ones like 17th century secondary sources and family tradition. So, if you come across something that doesn’t look quite right or conflicts with other sources, just know that Vivian does not represent gospel.
This is true in general for the printed Visitations. If you bother to read the introductions to these books, or even just the titles, you will realize just how much has been added on to the actual Visitation statement. Some closely follow the individual’s statement as to their family history, while others felt free to expand on them. Vivian, by far, of the printed Visitations, went beyond the actual Visitation. And so, just due to the number of additions is bound to have more errors.
PS: I maintain a list of the Visitations and other medieval sources I commonly use. This includes the Visitations by county and by Harleian Society Visitation Series number. I haven’t looked to update it in a while, so if anyone knows of other internet copies or can fill in missing volumes, I would like to hear from you.
PSS: I really just wanted to add a reply to John Atkinson rather than a new answer. However, when I hit that link I did not get any of the tools to imbed links, bold, italicize, control font, etc. Is that the way it is supposed to work? or did my computer glitch?