Flysky != FrSky
but seriously, telemetry/sensors are the "wild west". all the different manufacturers use different telemetry protocols, some have more than one (FrSky D series is different from X/L/R series), and they all use different methods to get the data back to the receiver. to the point where you will not be able to use a different manufacturer's sensors. Castle Creations make Speed controls that work with Spektrum OR Futaba, but to do so, you need an adapter (unique to the brand of transmitter) that costs as much as the speed control. One of the reasons i went with FrSky is because their sensor lineup is very large, and inexpensive. it also doesn't hurt that their protocol has been reverse engineered, and one can create unique/new/different sensors using an arduino.
from what i have just read, the sensors for the 6 channel flysky receiver will not work with the 10 channel receiver !?!?!