First impressions:

I have no idea how they measure anything like the chu. They sound totally different to my ears.

Not sure if is the fit, or the characteristics of the included ear-tips but they make these IEM sound bloated and muddy to my ears. That immediately went away with different eartips.

trying the spinfit tips that come with the chu have exactly the opposite problem: treble extension too sharp. very fatiguing.

With these short wide tips (pictured) the bass and mids sound tight, and the treble is really quite forward (maybe a tad too much so, not sure yet).

Independently from that, to me the timbre sounds much more natural than the Aria. Those also lacked in the treble for me- and hihats kinda got lost. (easy fix with a smidgen of EQ but not needed here).

I don't have 'truly' analytical IEMs to compare them too, but as far as I am concerned these display a lot of detail. Flamenco guitars sound just lovely. More complicated instrument arrangements can get a bit overwhelming.

I never had IEMs where the sound depended that much on the eartip geometry.