I roast on a Diedrich IR-12 for a busy coffee shop and some wholesale business. I find that the roaster gives me a lot of control over the roasts, as well as good temp readings, air flow, and gas control. The capacity is just right, to a little too much. I would probably be just as happy with an IR-7 or and IR-3. It is hard to control sample batches in the IR-12, anything under a pound requires attention and doesn't come out even all the time. So, depending on how much you need to roast at a given time, I would reccomend either Diedrich roaster.
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