I'm seeing the Ethos 21mm is on "sale" for $854. That's more than twice as much as any of my other ep's, which I already consider expensive. However...
My Pentax 30mm XW I like in general, except it seems that the wide exit pupil really shows my astigmatism as an annoying inability to focus to pinpoint. I either get an annoying spike at the 4 o' clock position, or slightly out of focus star. I feel either way is a compromise and it's annoying and frustrating. I hate that my eyes can't take full advantage of this awesome ep. And after using the 100° and 82° ep's, 70° feels a bit tight.
At just a slightly smaller tfov, but a much larger afov, the ES100° 20mm gets more use than my 30mm XW. I actually mostly use the 30mm when the 20mm fogs up. It's sharper to my astigmatic eye and I like the greater mag and the much wider view. I use a paracor 2 so both are sharp to the edge afaict. But the 20mm background is much brighter than the 30mm for some reason. I figure it's some sort of optical malady due to design. That's it's major drawback for me. Also, if I flip the rubber cup out, I cannot see the field stop so I never use it.
I find the two ep's to be redundant due to almost identical tfov. I'm thinking about selling both and getting the optically E21. I've read it is optically superior to the ES100 and I definitely prefer 100° over 70° and the exit pupil should be similar to the ES100 so as not to make my astigmatism apparent. I wouldn't break even, but it'd be close enough to consider it a wash for me. Am I overlooking something? Would this be a grievous mistake?