They do ok. They are advertised as working with a 300ft line of site. Mine are setup about 75-100ft away through a window and work consistently but any farther or any extra obstructions and they start dropping the connection. I'm going to try moving the sensor to a less dense compost pile today and see how it does.
With the sensor in the less dense but about 5 feet farther away pile, I'm able to read the temperature from inside the house