Our take: The JG factory enhanced piston with metal teeth and durable polymer construction is a great choice for high powered, high performance AEGs, whether as a replacement piston + piston head set, or as an upgrade. Full metal piston teeth optimize performance and durability, while polymer construction all around keeps weight down.
A ported polymer piston head is attached to the piston straight from the factory, resulting in optimized O-Ring expansion and overall better performance.
Disclaimer: Any and all Airsoft upgrade parts purchased from Airsoft Megastore will be used/installed at owner's discretion. Actual performance results depend on quality of installation, Airsoft AEG barrel length, tightness of the air nozzle seal, and other possible performance-affecting factors. We are not responsible for any damage that may occur with improper installation. For best results, please do all upgrades at a certified professional Airsoft technician/shop.