I've now put almost 100 hours on the Gustard R26 so I feel it's fair to compare it to the Pontus II at this point. So here goes ...
First of all, the R26 is a really really good DAC. I've owned more expensive DACs in my main system and the R26 will not be embarrassed in the company of DACs up to $3000 or even more. I was surprised by the clarity, drive, pinpoint imaging, and a soundstage that is by far the widest I've heard for an R2R dac with the exception of Terminator 2 which I also owned.
The streamer function, IMO, is average at best. I tried to compare it with two streamers -- Bluesound Node 2i (in my second system) and Aavik S-280 (main system). As expected, the Aavik blew it out of the water ... as it should since it's almost 10 times more expensive. But compared to the Node, the sound quality is more or less equal. I did experience some hiccups/buffering issues on R26 when feeding hi-res files to it. I would say that the LAN-based streaming function is good for the price but I would use it with an external streamer if I'm looking for the next level up. However, it is perfectly acceptable if you compare it with streamers around the $500 or below mark.
So how does it compare to Pountus II? Well, let me start by saying that it equals the Pontus and even exceeds in some areas. I'm actually torn between the two choices. Alas, I can only keep one. So what do I like about the R26? ...
Did I say, I love the soundstage? It is wide and extends way past the speakers on both left and right. The Pontus also has a decent soundstage but not quite as wide. The imaging is very precise and presents the music in a very detailed manner. The R26, at least in my system, is more forward sounding and prioritizes details retrieval and dynamics at the expense of a more tonally rich and denser presentation. The leading edges are sharper but are a bit too etched and pronounced for my taste. The bass is punchier but can sound thin (as in not quite as full and juicy as Pontus) at times. I think if you like rock, EDM, pop music you will be quite pleased with the R26. For some reason, it sounds less than a typical R2R dac if you ask me. But this is not necessarily a negative in my book. The DAC reminded me of Chord Qutest which I also owned for a few months and could not agree with the presentation style. I feel the Gustard has similar presentation but with more density and smoothness. It keeps the goodness of Quest but gets rid of the negative qualities. It kinda falls somewhere between the Qutest and Pontus in this respect.
So what did I NOT like about the R26 when compared to the Pountus? As I mentioned before, I found the R26 to be rather thin sounding but only when compared to the Pontus. The Pountus still has more of the R2R goodness that I really like -- more dense, tonally rich, juicy, organic sound. It's more focused on soundstage depth than width. Unlike the R26, the Pontus does not highlight individual instruments but presents it in a more cohesive manner, as if all the instruments are woven onto the same fabric. It just has a more heavy and solid foundation. For jazz, vocals, and acoustic music, I still prefer the Pountus II.
Looks: Of course, this is very subjective, but I love the understated elegance and simplicity of the Pontus. The R26 looks very 80'ish ... sort of like a set top box or a sleek VCR. But it's neither here nor there.
Given that most of the music I listen to is jazz, classical, vocals, etc., I'm leaning towards keeping the Pontus II and returning the Gustard. But there are times when the Gustard sounds so good and involving that I start second guessing my decision. Some songs, especially with electronic instruments or synthesizers sound extremely good and engaging on R26. Honestly, it's a close call. If I had not heard the Pontus, I would have been very happy with the Gustard.