1. It took 5 minutes to install, no joke. If you have a peephole already in the door, you just use the enclosed tool to remove the old peephole (30 seconds), insert the new peephole in the hole, hand tighten, and you are basically done.
2. Sticking through the door is basicly a decent peephole of the type you could buy for about $15 (which is why it fits the old hole) - so the overall image will not be better than that. The electronic viewer takes that peephole image, corrects the normal fisheye distortion, and projects it on a small blah quality LCD screen. The end result is an image much better than a normal peephole, but much worse than a "camera lcd screen" that the item description claims (unless you are talking about a 5 year old 1 megapixel point-and-shoot).
3. Although the image quality will not blow you away, it makes the peephole much more usable, and it prevents the person outside from using a reverse-peephole scope to see inside.
Overall, a nice security upgrade that you can easily install in minutes. The image quality is less than I had hoped (worse than the description seemed to promise), but I would buy it again in a minute.