Fil-C is only good if one needs to recompile an existing C program and gain extra safety without caring much about result performance. And even in such case I doubt it's useful, since existing code should be already well-tested and (almost) bug-free.
If new code needs to be written, there is no reason to use Fil-C, since better languages with build-in security mechanisms exist.
If new code needs to be written, there is no reason to use Fil-C, since better languages with build-in security mechanisms exist.