Many brewers use digital temperature control to monitor and control fermentations. In our opinion, immersion probes are overkill for these small conicals – and open another area for contamination risk. We know it doesn’t look as cool, but a liquid crystal thermometer on the outside is inexpensive and actually has the accuracy of an RTD (+/- 0.5F). We have measured the sidewall temperature versus core temperature at high krausen using precision instrumentation, and there is less than 1° difference – insignificant in reality. If you are using the probe for control, just tape the probe to the side of the tank using a small piece of aluminum duct tape. Again, you’ll be easily within 1°, and you have nothing to sanitize. In addition, this limits thermal cycling of your cooling equipment and overcooling that can happen with immersion probes. At Blichmann Engineering, we very much believe simple is better. While we would make more money selling you this equipment, our philosophy is to provide value. We would never recommend a product we wouldn't use in our own brewery.