The 4in1 covers the RTRs I've ran into, DSM*, FrSky, FlySky, Radiolink. SLT, Traxxas TRX4m have been added in the most recent firmware last March. Both versions play well with telemetry on each systems I've connected to it.
Ps. If you don't like the version you get, you can just buy the external module for the other. 4in1 version might be the better option in this case being that you could add a higher power, 1w or 2w, external ELRS module instead of the internal's limit of 250mw.