A lot of things come to mind when we think of Samsung (005930) smartphones, with big sales numbers, gigantic displays and sleek designs all near the top of the list. What we don’t think of, however, is class leading build quality and materials. While companies like HTC (2498), Apple (AAPL) and Nokia (NOK) continue to build increasingly impressive devices with sturdy materials and gorgeous designs, Samsung sticks to glossy, cheap-feeling plastics. Inferior feel doesn’t necessarily translate to inferior build quality though, and Samsung recently released a video highlighting some of the many stress tests it performs on its smartphones. Among the tests showcased in the video are home button stress testing with more than 200,000 presses, flex testing and the always important back pocket test where, in this case, a robotic rear donning denim sits on a Galaxy S III repeatedly. Samsung’s video follows below.