Hmmm. I have a lot of thoughts, but I'm still not confident in how I have them fitting. So any impressions are colored by my lack of a good fit (to say nothing of my lack of earbud experience and lack of comparisons to other earbuds). Take this all with a huge grain of salt, and know that my opinion will almost certainly change with time and experience.
That said, I don't find the
PolarNight at all dark. Warm? Yes. But dark? No. In fact, I was initially put off by how strident and forward the upper mids and lower treble were (with the stock donut foams). They initially sounded a lot like how
@o0genesis0o 's graph looks, with that very steep and very tall pinna gain region. The exact opposite of "dark." I didn't like them at first.
I then tried them without any foams and found the overall balance
much better, even if that almost entirely eliminated the bass response (no seal). Naked, the upper mid peak is subdued and the treble steps forward. But they lose their fit stability without foams. I've got silicone rings on the way so I can experiment more with a foam-less fit.
Then I went back to experimenting with the stock donuts. Now I've got them fitting securely and comfortably and sounding better than when I first tried them. The farther away they sit from my ear canal, the better they sound. Like with going foamless, that position tames the upper mids and brings up the treble (but not quite as much as going naked). The other advantage is that, unlike going foamless, I still get a decent bass response. Just means cranking up the volume a bit.
My current take is: they sound alright, but their big advantage over IEMs is their use case. They are perfect for walking. No occlusion effect, plus I gain situational awareness. But I'm going to keep experimenting with different foams, rings, and fits.
