"Protect From Import"

When exporting to SWF file, you can check the “Protect From Import” under the option setting window. My question is, how effective is this? Can you prevent people that download your SWF from editing it in Toon Boom Studio or even Adobe Flash? I know there are SWF decompiler out there but can the “Protect From Import” option protech my SWF file from being edited by others?