Given parameter name LENGTH defined as unit "in" in a part that have system units in "mm". If LENGTH has a value of 2 and you use the Evaluate Expression tool with relations the result returned is 50.8. I would prefer the result to be 2. As shown in figure below thou relations themself act different.
if length * 10 == 20
1 == 0\
/* Stop Regeneration if length * 10 = 20
has a Constraint violation. Because 2*10 does equal 20.
The system units for ANGULAR parameters are Radians, hense when you evaluate the result is in Radians regardless of parameter unit.
This makes it very difficult to evaluate complex expressions to determine if what you have done is correct or not.