Hello Geoff..........the only problem I've had with the spectrum system has to do with the antenna connection on the back of the transmitter module.....the connection has to be snug tight......but it is very easy to slightly bump the protruding connection and loosen it.........a slight loosening caused my reciever to go into hold.....the system recovered and the plane was landed safely............upon range checking after landing the "only slight loose connection" was found and normal range was restored by snuging up the connection..

needless to say , now on my pre-takeoff roll i double check the antenna connection for tightness

David C