One downside is that there is no locking feature on the ocular lens, so turning the power adjustment ring too far can loosen the lens.
I agree on the LER eyepiece. Poor eye relief is a problem with many (most) variable power spotters. That was the main reason I bought the Minox.
Paul
I had the same problem until I made a couple wraps with some electrical tape. Problem solved.
+1 on the LER eyepiece, mucho better.