I received my TEAC NT-505 yesterday and had a chance to do some listening last night. Here are my first impressions compared to my Node 2, which was using my Auralic Vega DAC (via coax) instead of the Node 2's internal DAC.
The NT-505 has a larger soundstage, better imaging, is more detailed, and is slightly warmer. I know the Node 2 sounded better with the Vega than it's internal DAC, so it's a definite step up from the Node 2. I have no way of saying how much difference the streamer itself made, as there's no way to connect the NT-505 to an external DAC, so I couldn't try it with the Vega as the DAC for a more "apples to apples" comparison.
I can't say that any of the improvements were "dramatic", they were all subtle, but do add up to a better listening experience, at least on first blush. I can see myself spending more time doing "critical listening" while streaming. Most of the time, I have used the Node 2 as background music, or to play music from my network.
Whenever I make changes to my system it usually takes a while before I notice all the little nuances, so I'm looking forward to spending more time with it.
Is it worth four times the cost of a Node 2? I think it will be over the long run, but that's up to the individual.
The Lumin software (I'm using that instead of TEAC's) was a little confusing at first, but I like that it just hooked up to the NT-505 right away, you don't have to go through the process of connecting to the unit like you do with the Bluesound devices. I wish it had Radio Paradise, but other than that, I think it meets my needs. It didn't take me long to get familiar with the interface, but I don't think it's as intuitive as the Bluesound app. As time allows I'll play around with some of the upsampling features and may get the Master Clock Generator at some point.