If it's an older model it probably has the temperature knob, instead of the digital screen button set method. It's my understanding they changed to the buttons for the heat fluctuation/leveling problem. Don't hold me to it but it seems I read that somewhere.
I have both. The 9200 (which looks like it has an oven element around the bottom of the lid and a turn dial for temp) and the 9300 (which has a small box heater on the bottom of the lid and a digital temp screen.)
I've only used the 9200 so far. It's REALLY hard to adjust temps without over-doing it. I tried putting a different dial on it but gave up.
How do people like the digital versions? For some reason it scares me. I don't know why.