I own the Sukhoi that Troy Built Models custom built,& I can assure you that the performance @21.75 lbs. w/ZDZ 80 is nothing short of amazing.This aircraft was custom modified for me by Gene for IMAC competition & is the only one like it anywhere.Gene is a master at making planes LIGHT!!& balanced for max performance..I am getting ready to offer this aircraft for sale as I am not going to pursue IMAC competition.If anyone is interested in it you can e-mail me, at thustonsmi at aol.com