I own the 1More and several Custom Art models, so I'd like to chime in. It seems like you're a big fan of the 1More since you cited its tuning by an Italian Grammy winning sound engineer. I'm positive a lot of companies have renowned sound engineers on their teams, they just don't need to market that information as aggressively as a newer company. I'm also a bit confused about the sound signature you're looking for, and I also think you might be misinformed about a few things.
A three driver IEM isn't necessarily better than a one driver; it's a misconception that more drivers = better. One of the most famous and beloved IEMs on Head-Fi is the Etymotic ER4S, which has just one driver (although it is a $300 product). It's a neutral/analytical IEM though, and it seems like you prefer v-shaped IEMs like the 1More, so I'm not sure if that would be something you would like.
Also, be wary of comparing graphs from different sources. Different reviewers will measure IEMs differently, so it's not right to compare a graph from Headflux with a graph from Custom Art. Maybe find a source with measurements of the IEMs you want to compare, like
@crinacle's
thread. His 1More and Ei.xx graphs are quite similar, except the Ei.xx appears to have smoother treble.
As you already mentioned, graphs don't tell the entire story; tuning matters much more. 1More has like a +10dB bass boost but it doesn't necessarily feel that way because of how fast it decays. It has elevated treble, which can contribute to clarity and separation, but that can be fatiguing for some over longer periods of listening, and you can have great clarity and separation through good tuning, rather than elevated treble. It's interesting that a lot of the reviews on Head-Fi state that the 1More is a balanced IEM, even though its graph shows it's quite v-shaped (which I agree with). In general, the average consumer appreciates a v-shaped sound, because elevated bass (for the wub wub wub and thump thump thump) and treble (for the feeling of clarity) can be appreciated more readily than a well-tuned midrange. The average consumer also won't be wearing their headphones for hours on end, so treble fatigue isn't as much of an issue. That's why the 1More is tuned as v-shaped: to have an very agreeable sound. At its $100 price point, it is still catering quite a bit to a casual audience. You can give a more casual listener a very expensive balanced/neutral IEM without telling them what it is, and they might find it boring and might even prefer the 1More's v-shaped tuning.
I own the 1More too and I think it's very fun, and a great IEM, especially for $100, but in my opinion, it's overhyped as one of the best IEMs in recent memory, when I think it's just one of the best IEMs for its price in recent memory. I'm relieved it's still less hyped than the TFZ Series 3 (look that one up for some laughs). I'm not satisfied with how quickly the 1More's bass decays, but more importantly, I think its midrange sounds slightly hollow and less lifelike (perhaps I'm spoiled by Custom Art products, which have some of the best midrange tuning you'll find anywhere). Then again, it all comes down to personal preference, and the 1More might even be end-game for a lot of people out in the wild.
Apologies for the long message! The 1More is a steal at $100, but I think you're putting a bit too much stock in its capabilities, especially compared to Custom Art products, which are steals in their own right and are tuned with very different intentions, for a very different audience.
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