"Slightly" sensitive is nothing to worry about. There is no law saying that you have to set the plane up that sensitive; the Hobby Lobby Sensitivity Police won't be kicking in your door

If you happen to have a nice transmitter with dual rates, you can set the plane up according to the instructions, then "dial down" the control throws to 50% or so on low rates. When you get up high and want to play, flip the switch(es) back to high rates.