Hi,
I know that there is interest for measures in Cheetah3D. Originally I thought that measures aren't that important because if you work unit less you can think in meters or inches are whatever you need.
If you finally want to export the model you can still change the units by setting the "export scale" factors of the file exporters.
I plan to add units to Cheetah3D but that feature has a quite low priority at the moment. Sorry.
By,
Martin