The only LER 10mm I am aware of is the Radian, but they are pricey($170 each roughly) and I have read that they are mediocre at best. With this focal length being solely for planetary I want reliable performance.
The lead contender for the 12mm slot is the HD-60. I have had a 12mm Paradigm in the past that I used cyclops style but sold it as the eye relief was barely tight enough to not be comfortable with my glasses on(my preferred way as I have astigmatism in both eyes). Loved that eyepiece otherwise.
I also would rather have eyepiece pairs than have another barlow. My collection has always been very spartan, but lately want to get a bigger EP collection. As you can tell my current eyepieces I don't need or care for wide field eyepieces. Performance and price are my main factors in selection.
Here are my current lineup with their binoviewing magnifications:
25mm hd ortho (61x and 107x)
15mm Paradigm (102x and 178x)
12mm would provide 127x and 222x < I think this is the better focal length to get first.(highest mag used last Mars opposition)
10mm would provide 150x and 262x < Eventually want to get this for rare max magnification use like favorable Mars oppositions.
This is in a 6" f/5(750mm) with a 2x WO OCA and a barlow with an effective 3.5x.
Also as a refresher, the last Mars opposition had a low altitude and a worldwide dust storm that ruined contrast.
Thanks for talking bino pairs with me!