Well, sort of a beginning: I decided to nose, but not taste (yet) Rain, Luksusowa and Wyborowa. Again these are distilled respectively from organic corn, potatos and rye.
This was very interesting. The corn vodka has a faint but quite noticeable flowery/vanilla-like note, almost (and this may sound odd) like a couple of moonshines I've tasted one of which was made from corn. Of course this isn't moonshine by any stretch, but the faint flowery note reminded me of new cereal spirit (which this is). Probably the scent would be much stronger if it had been distilled at 160 proof or under instead of 190+ but the weak nose subsists nonetheless. Is it corn-like? Not really. It went through many distillations and perhaps some filtering(s) so I guess it is possible the flowery note came from something other than the corn. The nose, delicate as it is, is intriguing and refined (nothing like I get from, say, Mellow Corn).
The rye vodka has the faintest note of (sorry Dave) damask. Really. Of course I've noted this, but with much greater intensity, in most rye whiskeys and some rye-recipe bourbons although (somewhat oddly again) when these are well-aged. But possibly young rye spirit has it too. In fact, the Isaiha Morgan rye does have it and this vodka reminds me of its nose but of course in a much less intense way.
As for the potato vodka. It smells of ... ethanol. I can't get potato or any other kind of vegetable, or any cereal-like, smell from it. It has a good round smell, not harsh and medicinal alcohol-like, but nothing that reminds me of spuds.
I decided to do this because to nose and taste them blindly with any sense of purpose I think I will have to have tasted the products before. Otherwise I have no reference point. I am pretty sure I can pick these out later, blind. Maybe they will taste like they nose, maybe not. Stay tuned.