Final comfort will depend mainly on concha and ear canal shape and size.
UM3X/SE535/W4 are all designed to sit tightly inside the ear concha, whose shape varies a lot.
I can wear SE535Ltd for hours with any discomfort (they rest very naturally into my ears concha), while W4 and UM3X annoy the hell out my ears after 30min because their nozzles are not angled properly for my ears canals, so the housings are not in the position they're designed to be.
And I'm sure we'll find the same number of people having exactly the opposite experience.
Everything not custom-moulded won't be ergonomic per say, even semi-universals like ASG-1.
But it's undeniable that the SE535 have sharp points compared to the the Westone and UM series.