The Nikon 550 reads accurately out to 550 yards, hence the model number. I've never pushed the limit but I used mine out close to 400 yards andit acquired every target without a problem. I'm not sure what constitutes a reflective target like Bob said his bushnell advertises but I was ranging things like trees, palmettos and clumps of grass at those distances. My hunting partner bought the bushnell and when he tried mine he said that he wished that he spent the extra money and bought the nikon. The quality of the image might not be as good as using binoculars but its good enough that I usually leave them in the truck. I bought mine at Bass Pro Shops, they have all of the different ones on display to try out and you can range stuffed animals out to over 100 yards.