Bought this microscope for my homeschooling 8-year-old granddaughter. I spent much of my career sitting in front of a microscope so I know a good microscope from a cheap one. This one is really nice. It has no design flaws that I have been able to notice. The resolution of the optics is quite good...much better than I was expecting. We have not yet used the 100x oil objective so I cannot comment on that one, but the other three are excellent quality optics and both the 10x and 25x objectives are good. The stage moves smoothly and the light is strong enough to get good visualization. The trinocular allows for a camera but also allows her and I to view the slides together and discuss them. My granddaughter loves it and is learning the joys of seeing the hidden details of her world. We wanted to get her a microscope that would last her through her college years and I believe we have accomplished that with this particular instrument. I would highly recommend it! Only downside (which is ridiculously minor) was the thin little plastic cover is totally inadequate, way to small to accomplish its purpose.