All piston heads are ported, it's a part of their function.
both are the same, the duracon is plastic and the aluminum piston head is well...obvious.
An aluminum piston head gives you better consistency in FPS and therefore better accuracy, but creates a harder impact on your cylinder head since it doesn't slightly deform like the plastic piston head. This COULD result in the shattering of your cylinder head or cracking of your gearbox shell. If you have a TM gun I would recommend a SILENT piston head set, still has a ball bearing, comes with cylinder, cylinder head and piston head, and reduces the force of impact on your cylinder head.
