It might very be the case that the show room (small hotel room) and the accompanying electronics were not ideal--they rarely are, but, I have some experience listening to gear under these circumstances so I have a rough handle on what the speakers sound like. I heard them in near-field conditions, so I know a bit more than if I heard them in some very large space where bad sound is most often the result of a bad room.
Please don't misunderstand, I actually liked the speaker. I am also very much drawn to speakers that sound vivid, alive and do micro-dynamics well (which IS the case of the Nenuphar). But, I pointed out what I saw as some shortcomings (all speakers have them) because that is, to me, more informative than unconditional ravings. Because speakers like the Nenuphar deliver a sound that is so much more vivid than the typical audiophile speaker, it is easy to be caught up in its strengths and not become aware of what would be more serious issues if you own them and had to live with them in the long term. I did that myself when I first became aware of what many high efficiency systems (e.g. horn systems) can do.
By the way, I find it interesting that you mentioned the S.I.T-3 amp. A friend of mine built his own S.I.T. amp from the design Nelson Pass made publicly available and it is one of a handful of solid state amps that I like. Another one is the Nelson Pass First Watt J-2 which I borrowed from the same friend. I would not consider either amp "warm," at least tonally, but, they were very musically engaging and did not sound lifeless (which is the case with many solid state amps).