I assume they made the Drone in FLX plastic because it was easier to get it to weigh up than in stiffer ESP. I don't like the FLX plastic becase I think I can actually feel the disc warping into an elliptical shape as I pull it across my chest.
Hopefully they will get some Viagra into the plastic on the next run to get these things aroused into stiffness and ready to hold up in the hand during the pull...
