I would not attempt to fly. My DX-7 range checks great well beyond 30 paces (90 feet or so for a typical adult I'd think) and that's with both the 6200 and 7000 Receivers.

Since your buddies transmitter range checks fine with your receiver, I'd bet you have a transmitter issue. Contact Horizon and they will take care of it.

Once yu get the transmitter sorted out, double check your receiver installation making sure the antenas are oriented correctly just to be on the safe side.