The stock firmware of a 9x is all but unusable for multirotors. The RF module and receivers are crap. But a 9x with a frsky module and flashed with opentx/er9x is like a "taranis light". Fewer channels, dials and switches than a taranis, no voice (biggy imo) and limited telemetry functionality, but still extremely programmable and quite a decent radio for multirotors, especially if you use OSD. Problem is that flashing isnt easy, to put it mildly.
Another option would be the 9XR Pro, which solves most of the problems of the 9x (already runs opentx, has audio and telemetry) and is still cheaper. But I find you sacrifice a fair amount of functionality and quality compared to the taranis, for a modest financial gain.
My 2 cents; if you dont want to spend the money on a taranis (and be set for many years), then find a second hand 9X thats already flashed, and if you're lucky, perhaps has lcd backlight, audio, and telemetry mods installed.