I use a Bluesound Node 2 via Wi-Fi for a small system in the bedroom as well as a Node 2i in my main stereo system using an Ethernet connection. I stream digital files from a NAS drive and really enjoy having access to all my ripped CDs and Hi-Res downloads. But I don't have experience streaming from a Vault. Having the Vault 2i connected via Ethernet should help.
The Wi-Fi capabilities were pretty bad with BluOS for a while but got much better in the past 6 months, at least in my experience. Far fewer drop-outs, even with a "FAIR" Wi-Fi connection to the Node 2. But again, that's streaming from a NAS drive, not a Vault. Try it though and you might find that it works just fine.
Tom