Although the TE-20H 25X LER is fine for any pistol caliber from the 25 and 50 yard line, to see the holes left by a 22 at 100 yards, 40X or 50X power is necessary. The TE-10Z 20-60X zoom eyepiece is great for the 22 caliber out to 100 yards. Of course larger calibers are even easier to see and require less magnification. I don't try to use the full 60X because the depth of field is so narrow that unless the paper target is exactly at a right angle to the trajectory, there is distortion. The zoom mechanism is smooth and offers sufficient resistance to make adjustments easy. I rarely use my other eyepieces since getting this one.
Pros: Quality consistent with 883 Kowa scope with which it mates
This review was written in the old system and had content requirements that are different than reviews written today.