I am getting back into rc after being out for a while. I live in central Florida and was at the Winternats last week. It was great! I just won a used MRX4 with motor and starterbox from ebay. I also picked up a used set of Hudy alignment gauges. My question is should I buy a new spetrum radio with the telemetry or get a good used radio 3pk or M8 ? Do you need the third channel for the transponder? What else are high priority items? For servos I am looking at savox sc-1257. Any thoughts comments?