IMO westone has the most comfortable universal IEMs in the market today, i try several IEMs and even the 64 audio IEMs with Apex are less comfortable and less suitable for long listening sesions.
I have the U4SE and despite the apex module these produce ear fatigue in long sessions....
With my W80s the ear fatigue is reduced to nothing in the longest listening sessions.
(I will not compare the sound quality of both IEMs, but despite the price gap, these U4 are surprisingly very good, so good are they, I'm seriously thinking about buying the U18)
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