A classic. Its origins are probably in that guitar instrumental that Lindsey played during the Buckingham Nicks sets, although that and NGBA are not exactly identical. On the album it's just the right length, and it remained at that length when they played it live as a band with John on acoustic bass. The SYW versions were a first of sorts with Stevie harmonising on them, I don't think she ever did that on NGBA before.
However, once the tempo got slowed down on the Tusk tour it became more moving to me, a little bit of faux-drama never hurt anyone.
Those remain my favourite versions.
The Rumours DVD-A version has that great extra guitar track on top, Lindsey stated that they first wanted to make it more layered but decided to keep it stripped down. Something in me wishes that they had first taken the add-more-overdubs route, who knows how it might have turned out! And then later on Lindsey could've stripped it down like he's done with some of his other tracks.