Interesting the many struggles with the FPS. Mine (S10, Verizon) was a little screwy the first night, but since then, works great. Probably 95% success rate hitting it first try. I followed some tips I read online about setting my most used finger twice as both Finger 1 and Finger 2. Tap on the screen where prompted, and leave it there until it unlocks, and it does so virtually every time. Even at that, the other fingers I only registered once as Fingers 3 and 4 seem to work fine as well when I use them.