acct0283476 said:
The old policy, if I remember correctly, was that the ideal was to use an artist's real name if it was acquirable, as that would be unchanging (99.9% of the time), whereas many artists go through several aliases. The idea being to have the least hassle in setting up aliases for changing artist names, since then each new name could just be aliased back to the real name, instead of shifting aliases again and again whenever a new name is used.

This is just my opinion and in no way official but personally I prefer having the most commonly used aliased used. For example, if all of Os's artwork has the signature Os, has an FA account called Os, and basically always goes as Os, i'd rather have the tag os than joshua_frinkle.