Both Find and FindChild methods search for the needed object (with the specified values of the specified properties) in the hierarchy of objects.
The only difference is that the Find method starts from the object whose method you call while the FindChild method starts from the object's children.
Please see the "Find Method" and "FindChild Method" help topics for more information.
>> it takes FindChild twice the amount of time it takes the Find method to find an object
You can face this behavior if the object whose method you call suites search criteria. In this case, the Find method returns immediately while the FindChild method might work much longer.
If this is not the case, please let us know in what case the FindChild method works longer than the Find method. We will investigate this behavior.