Been using this project in it's current configuration for ~6 months now without any issues. Definitely had some concern that there would be drift or complete failure of the smoke detector sensor due to the high-grease environment, but nothing yet. I haven't even needed to adjust my parameters for controlling the fan based on temperature or smoke levels, which was surprising.

Been one of those rare projects where it just works! I've been very happy with the responsiveness whenever any cooking begins, it's ramp-up as conditions worsen and with how long it runs after cooking stops. An absolute improvement over manual control of the exhaust fan.