[pizzainthemorning]

So I've been running my gun on a PDI 170 for a few years now and keep eating mechbox shells, gears, and pistons. I know, I should get it fixed up properly by a gunsmith, but that's not really an option. So, I'm ordering some more parts and was was hoping to figure out the following:
1. Will the parts be compatible
2. Will the parts be sufficient to run a PDI 170

Systema Reinforced Mechbox
6mm (I think) Steel Bushings
Systema Silicon Piston Head with Bearing
Guarder Infinite Torque Up Gears
Guarder Half Tooth Polycarbonate Piston
PDI 170 (of course)

Everything else on the gun is stock and has been fine thus far. I'm not looking for performance, just durability. I want a solid beast.

Will the systema piston head be compatible with a guarder piston?
Should the piston be half tooth, or will full teeth work fine also?
I've read good and bad about aluminum pistons... opinions?
Is a silent headset necessary, or will a silicon piston head be enough to prevent mechbox breakage?

Thanks,
Alex