The reason that I like my Pentax eyepieces so much is the long eye relief. With my bad astigmatism I can leave my glasses on with any of the focal lengths and see the entire 65 degree field of view clearly. I have yet to look through any other eyepiece and see the whole field of view comfortably with my glasses on. I did indeed sell all of my Naglers and trade them in for Pentax eyepieces for this reason. For higher powers I still like the Meade Ultra Wide Angle eyepieces better than the Naglers I've looked through. I seem to get flatter, sharper images, yet I know that everyone's eyes are different. For the very best planetary views at higher powers, I feel it's hard to beat a high quality orthoscopic eyepiece with a 12.5, 9, or 6mm focal length. Thanks. Lowell