The zoom is controlled with the knurled knob at the top of the microscope. The cable passes through the centre of this knob. One reviewer said this might wear the cable. The knob takes many turns to zoom through the whole range, so it's a bit troublesome.
The stand was sold separately, but it's VERY important. Especially since its rack and pinion design is similar to a "real" microscope stand, which lets you easily move it closer or further. One of the reviews for another microscope on Amazon said its ball and socket stand was hard to focus.
One of the reviews said its software was slow to update in real time. Ideally, microscopes should have 2 modes - a low-resolution fast one for positioning, and a full-resolution slow one for taking pictures. I'm glad to say, for me, the software was fast. But taking pictures is VERY slow. It takes at least 3 seconds after pressing the shutter to take a picture, by which time the microscope would surely have moved if it was being handheld, making the stand necessary. Videos don't seem to work - the quality doesn't change and framerate remains at 5 FPS no matter what settings I use.
Ok, this is the real measure of the microscope. Firstly, it's clearly able to zoom in more than any of my cameras, or in fact any camera I've seen. It's able to resolve details my camera can't.
I have to say the image quality isn't very good. There's a lot of chromatic aberration, as you can see from the pictures. The top left corner always seems out of focus (see the ruler picture). Could the lens be out of alignment? Pictures also don't seem very sharp, even when in focus.
To be fair to this microscope, microscopy isn't something you can just pick up subjects for. The microscope pictures we're used to seeing have had hours of preparation and tens, possibly hundreds of rejected pictures before this. We're just too used to phone cameras and being able to pull out a camera and take a picture of whatever we like, expecting a sharp, clear image. I think if I spent more time preparing, I'd have a better idea of this microscope's capabilities.
Oh, when you zoom out to the minimum magnification, everything further than ~30 cm away is in focus, so you can actually use this as a webcam!
It's available on Amazon: http://www.amazon.com/Supereyes-B008-Microscope-Endoscope-Magnifier/dp/B0066H7H1Q/