Interface strain gage load cells are the most reliable and accurate sensor for measuring force, as it's specifically designed to capture the total mechanical load. In contrast, a pressure sensor is designed to measure force distributed over a known area. While it is possible to design a load cell to measure pressure like Interface's IPCD, load cells are commonly used because they are specifically engineered and calibrated to measure total force accurately. Attempting to measure force with a standard pressure sensor is problematic because its output depends on both the force and the area over which it's applied. If the force distribution changes, the sensor's reading will change even if the total force remains constant. This makes a pressure sensor an unreliable tool for measuring the total force applied by a solid object.