Spotify artist links


What is the recommended format for Spotify artist links?
For example both


take you to a Spotify page about Radiohead although each one has a slightly different format.
I have seen either one being used on most artists and there are a few artists that have links in both formats. Is there a reason why one would be preferred over the other?


Will be automatically cleaned up after the 2017-02-13 release (sooner on beta).