I understand. I'm a CIEM-er myself.
I think you've been wise to think very carefully before choosing a CIEM, but if I were you, I'd now take a step back and forget about it for a few weeks. Completely ignore the topic. When one first enters the world of CIEMs, it can be like a game of leap-frog; you find a review that says such-&-such CIEM is the best since sliced bread, and you get all enthusiastic that it's the best one for you, then you see another review that says this CIEM is the best thing since sliced bread with jam and cream on top, and it seems like the best choice for you, etc. etc. And in the end, you just end up in a whirlwind of confusing options, losing sight of your original priorities, and becoming disheartened.
At the moment, you're trying to do all of this deciding by using your conscious mind, and the conscious mind is easily overwhelmed.
If you stop trying to think consciously about it, you'll be surprised what your subconscious mind will do to figure things out. Things will begin to snap into focus and your priorities will become much clearer.
Then, with clearer priorities, you will be able to re-enter the topic and make a wiser choice based upon the closest fit between your priorities and the sound character of each of the available CIEMs.
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