FWIW, the discussion about IR probes is way off.
1) All digital sensors must use "an algorithm" to read values. A thermocouple does not just send back raw temperature numbers to the computer, it sends back voltage readings that then must be converted to temperatures. The IR sensor driver code is almost identical to one from a thermocouple code since the vast majority of code used has more to do with bit twiddling than anything else. You don't have to take my word for it though, just look at this open source driver for arduino: https://github.com/sparkfun/SparkFun_ML ... X90614.cpp
To be very clear, IR sensors provide definite latency gains compared with similarly priced/quality thermocouples. Light travels much much faster than a sheath of metal changes temperature.
2) The concerns about emissivity and background temps of the IR probes strikes me as incredibly pedantic even for HB. Very simple IR thermometers that cost under $10 have no problem detecting the temperature of random items to a high degree of accuracy, I see no reason why the IR probe in the bullet can't do the same. IR technology has been around for a while now and is largely a solved problem for most problems of a reasonable scale. The IR probe is not perfect and will have its own difficulties, problems, nuances, and quirks, but most of the concerns in here seem unfounded. By far the #1 issue with IR is emissivity calibration, and Aillio seems to have solved that issue well enough. Here is a thread where Jonas addressed many questions (including my own that were in the same vein as some asked here, although I was more curious than critical) about the IR probe: Aillio Infrared Bean Temperature Sensor IBTS
3) The IR probe is definitely tricky to get used to, but I think once I get a handle on it I'll be able to make much better decisions about roast adjustments than I was with a 3mm probe. My own personal experience has shown it to be remarkably accurate for yellowing, FC, and 2C temps largely regardless of environmental factors.