Its always important that when using a Professional Hanging Service that they use the Right Hook to hang pictures with. Lately I have come across professional installs that use Brass Plated Picture Hanging Angle Drive Hooks in plasterboard walls. Though these do work and are readily available at Bunnings they are going to loosen up after a while and in a recent install I did come loose and have to be replaced.
I offered to reinstall my clients "Professional Art Install" that they had prior with correct plasterboard mounts and button head screws so they would never come loose. If you see an Art installer using these then its not done correctly.
