I have a Bluesound Vault 2, but also a Node (original N100) on two separate systems. I run both with Android tablets (or my phone or desktop PC), have about 550GB of music on my network and subscribe to Tidal Hi-Fi. It all works really well. Bluesound will soon have integration with Roon, as it's all signed off with the Bluesound team and in the hands of the Roon people to integrate it.
The ability of the BlueOS to create and save playlists that can be a combination of songs from Tidal Hi-Fi and my own library of music is great. I'm more inclined to listen to entire albums than to playlists of individual songs. Another thing I like is that I can pull saved playlists and use them from either device. I can have the play queue (whatever is currently playing) "follow me" from one system to the other, or link them to play a single source on both systems at the same time.
My receiver is an NAD T758 and I just upgraded the video card (MDC module) to the 4K one. What this now does is allow me to get the BlueOS kit & license so I can move the Vault to where the Node is, run BlueOS direct from my receiver, gift the Node to a family member and have one less component on the entertainment center/rack. The fact that all devices are MQA compatible is nice, but true that there's little content out there and the future of it is uncertain. I notice a difference with the few MQA files I have, though I wouldn't consider it to be "profoundly" better.
As to streaming rates, Tidal Hi-Fi seems to the only one for now. Spotify Premium is 320kbps and most people can't tell the difference between it and Tidal Hi-Fi's 1141kbps. Truthfully, I doubt I can but take comfort in knowing I have the best.
KEF R500, R200C, R100, R50, SVS SB2000 sub, NAD T758v3 AVR, LG UP875 4K BlueRay, Samsung UN55JU6500F 4K LED TV, KEF M500 headphones, Sony CDP-CE500 CD changer. Office: NAD M10, KEF LS50, KEF Kube 10b, Pro-Ject RPM1 TT w/ Ortofon 2M Red. Guest room: Hafler 300 L-R, KEF Reference Model 100 center, KEF iQ10 surrounds, modded M&K V-90 sub, Bluesound Vault 2.