So i've decided to build my first DMR. I've built a couple of speed guns in the past but never a DMR. I need your opinion whether or not I should use some of the parts I have laying around. My target FPS is 500 I have 2 sets of KWA 2GX gears laying around, should I just use that and kwa's piston+metal non-ported piston head or purchase SHS 32:1 and new piston+ported plastic piston head. KWA claims that the gears are high torque on their site.