The mistake I often made was trying to use it in too low light. I pushed it to 26500iso a couple of times with actually fairly passable results, but had I realised at the time I was working outside of the limitations of my equipment I probably wouldn't have bothered trying. The light meter in the camera I was using just didn't work down to the levels of light I thought I could shoot in, at the time it didn't cross my mind...
Anyway, that's not to discourage you from using it... Just giving you a mistake I made to learn from
It's quite grainy and the results are fairly high contrast, which is good for the dull low light situations you might want to use it in. Metering off skin tone is a good place to start in low light as it provides a good average ... Lightmeters are easily fooled and can provide confusing/overwhelming results if you are in a situation when light sources are points of light surrounded by dark. Eg point the meter directly at a candle then at a dark bit of room behind it and see the variation ... In that situation, spot metering directly off the persons face lit by the candle is the way to get a good exposure. Slightly simplistic