I almost went for the Eclipse, but ultimately decided on the Venus since I prefer open backs overall. Not sure how many Eclipse are out in the wild, but the 2-tone wood aesthetic and unique chamber design to make it sound as "open" as possible is very intriguing. If I was looking for closed, these would get some serious consideration, especially given how impressive the Venus sounds.
I did see that post and intended to reply, but forgot about it I guess.
Anyway, I no longer have the Jupiter so could not do a direct comparison, so take this with a grain of salt. The tuning of the Venus is definitely on the warmer side, anchored by a deeper, more impactful low end. They are a bit v-shaped, but pretty well balanced overall to my ears. I do not find mids to be recessed at all, and are not too forward sounding in the upper mids. Despite an uptick in the upper mids/lower treble, I detect no harshness or fatigue in the upper registers. These are a very smooth, yet detailed listen.
From memory, Jupiter is the more neutral headphone with some warmth, but does not have the same authority in the bass as the Venus. Mids are very natural sounding on both and very similar in presentation. While still relatively smooth, I did hear the Jupiter as being a bit hotter in the treble region, which I did lead to some mild fatigue for me. Perhaps this is simply due to the fact that the bass wasn't as powerful, so the perception of more prominent, detailed highs was evident.
I honestly think you'd be happy with either, but I personally prefer the more romantic tuning of the Venus. Just an overall, more "fun" tuning for me that does well with rock music.