This is the Spektrum DX2S 2Ch DSM Surface Radio with Telemetry and 1SX. The Spektrum DX2S will tell you everything you need to know about your vehicle's performance, except how much you love it.
This is the Spektrum DX2.0DSM 2CH Radio w/SR300-no Sx
This is the Spektrum DX3.0 DSM 3-Channel Radio with SR300 - no Servo