This microscope is very good for the money. We have several Olympus, B&L, Nikon, and Zeiss scopes. Optics on this scope are pretty good. The objectives adjust so the scope can be set to parfocal. The eyepieces have a groove for an o-ring to seal them, but didn't include the o-ring, so if your work environment has lots of stuff flying around, you might want to add this. The focus rack is not quite as nice (a little crunchy) as the name brand scopes, but it works perfectly fine. The light is sufficient, although is slightly under powered with the .5 lens attached due to the increased working distance. The light works well at 4" though.I needed stereo scope with a small base and was comparing used name brand scopes to these. You can get a decent used scope for this price, but they often need realignment, which costs about $200 to be done professionally. Overall I am happy with the purchase.They did ship me a scope with a slightly different base, which I believe is a M-1BNX. I think the base I received is a little larger and has beveled edges. It works well for what I need so I didn't exchange it.I wish Amscope published the lumens for their light sources or at least listed which of their product are brighter than others in their product line. The number of LED's doesn't provide this information.This scope also did not include any sort of manual. It is relatively self explanatory, with the exception of setting the eyepieces to be parfocal. You should look this up if you don't know how.