Hello all, in case anyone has the FMS Yak 54 and is unhappy with the flight performance (namely the low power output for a 3d plane) I just wanted to say that I upgraded the ESC to an 80amp ESC and am using a 5s 3300mAH pack. Flight times are 6-7 minutes and vertical climb appears unlimited. Hovers nicely at 60% throttle and climbs out very easily and quickly. Motor gets warm on a 6 minute 3D routine but doesn't heat up at all on conservative sport flying. I have a motor upgrade ready to install but so far the stock 760kV motor seems to be holding its own lol. Happy landings!