I strongly believe in Micro Chipping Mid to Larger Parrots.
Legal: Parrots are considered 'Property' under near all legal systems worldwide. It provides clarity of ownership that bands cannot.
Travel (CITES): International Travel requires extensive documentation as to ownership. Micro Chip provides a confirm connection between your documentation and the Parrot.
Stolen /Fly Away: Both happen far more than one would believe. Micro Chip works every time someone scans your Parrot.
Long Life: Unlike Dogs and Cats, mid to large Parrots can live a very long time. The costs per year of potential life have Micro Chip costs far less for a Parrot than a Dog.
Life: Stuff happens all the time. Fire, Storm Damage, etc... and all your paperwork is gone, the Micro Chip provides a solid foundation to recover needed documentations - Proof of Ownership!
Fully Transferable: Ownership transfers are trackable! CITES requirement that becomes more important as the Parrot population ages.
Etc, etc, etc...: IMHO, why would one not Micro Chip!