Agreed, the difference is hardly noticeable.
The issue with Avgas is the build up of lead deposits causing hot spots on the turbine wheels.
As Shy Torque points out some engines are approved to run on diesel. i.e.(PW206/207). But be aware that the engine may be OK but in some cases the airframe is not. (EC135?)
In the High Arctic in Canada Winter Diesel and Jet is the same thing.