Japan's venerable Hozan Tool Company (since 1946) was among the first to commercialize a spoke tensiometer in the 1980's—C-737, see it here.
Shimano, in particular, has been partial to the Hozan tool in their many wheel assembly plants. You can't deny the importance of a JP tensiometer to the emerging wheel scene.
While we are biased to the Brandt designed Wheel Fanatyk model, most accomplished builders own more than one type of tensiometer. Why? For experimentation, cross checking, and the experience of using a variety of tool types.
Our interest was piqued when Hozan redesigned this device and added a digital indicator in June 2020. The C-738 is a fine improvement in several ways.