yeh i was just reading some threads on the flip, some like, some hate, alot say you need to cut the wing tips off for better performance, alot say it tips up and stalls out when landing, my f90 did that until i moved the cg, but they say regardless of cg it still does it, also sounds like the fx91 would be too heavy for it, those guys need to add weight to the tail with smaller motors, so the ucd is in the lead, unless i sell the 91 and get a saito 73 or 82, then there is alot of smaller planes out there, i don't want to do that though