No, only with the legs. I like tall loudspeakers.
DavidAVDavid, who has Sons and loves them, has confirmed that he prefers them with some sort of riser.
I did not see threaded inserts. Actually I did not care at all for how they were attached. Each leg is attached with three small screws. The attachment method looked appropriate for a lightweight coffee table, not for a heavy loudspeaker. I would've preferred a much more robust attachment method, and much heavier, sturdier legs.
PS: I like the Sons a lot. I have liked every field coil implementation I've heard (WvL, Classic, Songer, Treehaus) except the small Audio Note.