Don't forget to enter the correct "Lift Angle" otherwise the amplitude readings will be wrong. The values for the most common rep movements are: Miyota 9015 - 51deg, 2824/2836 - 53deg, 7750/7753 - 52deg and 6497/6498 - 44deg.
The limitations of these timegraphers (inc mine) is that they don't emit the actual sound of the escapement, so diagnosing balance faults and incorrect impulse jewel strikes are not possible. They're all basic tools for simple regulation and beat error correction. The advantage of the purpose timegrapher is that the microphone/watch holder is easily adjustable to measure readings in the 6 positions - dial up, dial down, crown up, crown down, 12 up and 12 down.