F-15,
I'm not trying to argue or discredit your LHS, but this isn't true. While it is true that a lot of times it is the crystal in a receiver that causes problems. But it is nowhere near 9 out of 10 times. There are a lot more problems that can and do occur in a receiver after a crash that happens. Cracked circuit boards, damaged electronic components, cracked solder joints, and many other problems can pop up. A range check is not a accurate test of the operation of a receiver that has been involved with a crash. As has been stated earlier in this thread, the only real way to know if your receiver is 100% operable is to send it in and have it serviced by a reputable repair facility. Many times problems with damaged receivers won't show up in a range check, but will show up when subjected to the rigors of flight.

Ken