Define best? Sonos sells their own, and Sanus models. Many people swear by Flexson, including myself. 
 

I’m not sure whether the rules for this forum allow posting of links for competing products, though. 

They do not, but I’m not sure if that applies to accessory products like stands.

Anyway, I think speaker stands fall under the furniture category, meaning that they are valued for objective functionality as well as subjective aesthetic value.   I don’t care for the aluminum look myself.

It’s just that the OP has placed exactly the same post in another place, which burgeons on advertising, IMHO. One post I could have tolerated, two starts the questions. 

Best looking I would say is:

https://www.gearpatrol.com/home/a37961998/floyd-sonos-speaker-stand/

but hard to come by

Looks like the designer got inspiration from a bent wire hanger.  

I’m fond of mine, very minimal look, very stable.

https://www.crutchfield.com/p_051WSS51B1/Sanus-WSS51-Black.html

I’m fond of the Flexson ones myself, although they look pretty similar to @Stanley_4 ‘s Sanus stands.

I’ve got a pair of them for my Fives, and two pairs for my PLAY:1 surrounds, and some of their desktop supports for the PLAY:1 that flank the monitor I’m looking at.

https://flexsonusa.com/collections/sonos-five/products/flexson-floor-stand-for-sonos-five-play-5-black

Sonos please bring back a version of the Floyd 5 speaker stands.