For the Watermark sensor, there is a lot of calibration data available to convert the measured resistance to soil water potential (kPa).
This data is used to compare the gypsum sensors under the same moisture and temperature conditions with the Watermark sensor.
Below is the comparison result.
The Watermark shows better sensitivity in the saturated to field capacity range.
Both sensor types share a slight temperature dependency.
In summary: both sensors types look very usable for irrigation control.