The angle viewfinder does its job well and is not complicated. For the price, it's as good as you can expect or want. The only change I could ask for is clearer indicators to show if the measured angle is left or right of the ideal vertical, as the triangular arrows on this device only point up or down, which is not an intuitive way, to show him. A diagram of an acute angle opening to the left or right would be much more intuitive. It's quite sensitive when tilted backwards (about 10 to 15 degrees backwards is enough to give an error), but it will at least show "Error" until it's properly aligned rather than giving false readings . I've had it for about 5 months and use it for about an hour once or twice a month - so far it's not heavy use but it's enough to tell mine hasn't died on its own and doesn't drain the battery quickly. when not in use. It's inexpensive and does the job well. If you are reading this review then these are probably the criteria you are looking for. If I needed a second inclinometer, I would buy another one.