Hello! The "T" receivers are our latest telemetry equipped versions. The 8 and 9 ch versions do allow SRXL connection, this is what the X+8 module connects to.

Our larger Power Safe versions of the telemetry receivers, (9,12,20) all feature SRXL as well. You do not gain much by adding the X+8 to the 20 ch version as this is basically built in. Your DX18 will work just fine on the 20 ch receiver.

please let me know if you have further questions.