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I'm on Gain 10, Offset 100, temp -25 and only use unbinned, unless framing or plate solving. 2x2 binning doesn't work very efficiently for this camera and is somewhat pointless for quality imaging data, but ok if you need fast download (as per examples above).
My simplistic explanation for gain/offset below. Gain is effectively slope and offset is intercept in an algebraic sense:
Offset - This value is added to all pixels. You need to make sure you never get negative or zero values read out - actually value doesn't really matter too much - anything above 100 or below 1000 is probably fine.
Gain - the multiplier you apply to all pixels. Too low and you won't "spread out" your incoming data over the full 16 bits (values of 0 to 65535), too high and you'll "clip" at 65535. You brightest stars should never be over 60000'ish in long exposures or you will lose colour saturation. Shooting a bright ceiling with a quick exposure is another technique.
Temperature - the reduction in noise drops off significantly once you're down to -20. The camera can do about 50-55 degrees celsius below ambient. Pick a temp that you will always be able to reach even on the hottest summer nights. For that matter, if you'll be shooting darks during the day in a dark cupboard, might be worth taking daytime temps into account too.
Once you get gain/offset in the ballpark, there is no reason to fiddle. Make sure you never have "fast downloads" selected in the driver - LOTS more noise.
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