Thinking of taking the plunge.

So if you already have a SPDIF coaxial non-USB DAC and you want to stream, I agree with the used BlueSound Node 2i. It’s reasonably inexpensive, only has SPDIF coax out and you can stream a multitude of platforms through it. If you want Roon, then do yourself a favor and build an Intel NUC with better than the minimum specs per the Roon ROCK info at Roonlabs.com. Buy the NUC, RAM and M.2 SSD on Amazon. Install Roon ROCK on it and try it out. That could be your Roon Core. If you want buy a linear power supply for it. Then get a one year subscription to Roon. You can use Roon remote on your phone or iPad. I suspect that you already have the headphone amp and or preamp/integrated amp and speakers covered. 

Larry,  I agree with your dealer that a better DAC will make more difference than say MQA v hi res on Qobuz. But I prefer the full MQA.  It is just my preference.   You really should try for yourself. The guys in Toronto at Audio Excellence Canada have some great YouTube’s on yodel v Qobuz and different streamers. And they agree that the dac in the new Bluesound is better than the 2i but the streamer is the same.      

Don’t minimize the importance of the user interface.  Bluesound is so easy to use right out of the box. Almost no learning curve. 

+1 on the Grace Digital Link.  It's a very good streamer for the price.  Amazon (U)HD has been a bit confusing on what it is streaming.  I've tried connecting my old Note 8 using USB output to my dac and bit rate is limited similar to the Grace Link.  24/44.  In the Grace+ app, I see MPEG4-ACC is being sent.  

I can Chromecast Qobuz to the Link with 16/44 (CD Quality) and sounds very good.  I have to listen harder to hear the difference with AMHD.  I've been trying to use 24/96 in Qobuz but not sure if it's my dac, Qobuz, or the Link causing the stutterring/static sound.  Grace Digital says it's not their device.  Qobuz says to increase the app cache to prevent stuttering.  The manufacturer of my dac is a bit responsive being an EU company.  

All in all, I would still recommend the Grace Link.  My next step would be to get a Raspberry Pi 4 since I've read that the usb out has significant improvement over the rpi3 where I wouldn't need the Allo Digione stack card.

I know in our hobby, 1's and 0's are bit different for us but working in IT I can't seem to spend the money on a $2k-4k streamer even though my DAC is $3k.  These new streamers are mini computers so I think a rpi4 would be just as good esepecially since I can use Roon or Volumio.