I've used photoresistors for hobby projects before, such as this one:
However, now I'm working on a commercial product that needs to sense when it's dark and I'm unsure of whether the circuit I designed on the above page is adequate. The reason I'm concerned is that in my experience photoresistors have very low tolerances (i.e. high deviations in photosensitivity).
If you were designing a low cost circuit that could output a HIGH logic level when dark and LOW logic level when light (or vice-versa), would you use a circuit with a photoresistor like the one I designed, or is there something else that is more reliable?