I would ask you a similar question, how much would you be willing to pay for Aurender V200? if it were 8k, would it be still ok, or say, 10k, or perhaps you would also admit 13k or more, still there will be some improvement in SQ? How you measure the limit in case you have one? This is what the marketing is about, if they see you eat it, they will further increase the price.
I think that the Node is fairly priced, it does it's elementary job to transmit the data. In fact, do you realize that the difference in SQ from one badly recorded composition to another fairly recorded one would be much more than in your 6k upgrade?
I will tell you a secret that, in fact, am very keen to compare the Node with these steamers, but there are no such dealers close by here where I live. And it is against my principles to pay 6k for a simple computer (i would, if it were day 2k, which is already five times more, since obviously it will not be worse than the Node). Honestly, i don't like these big screens in streamers, they attract your attention on non important things when you wish to concentrate just on music. And I guess these screens are half from the total price.