I thought I'd try out a cadence sensor on a gym bike with the indoor bike activity, but it seemed to cause problems in later activities on other equipment like Walk Indoor.
Every so often the watch would vibrate and switch to a screen with 0 Cadence displayed. I put the sensor in my bag on the other side of the gym so it was static turned off the sensor in the watch options and vibration, but it still persisted. The speed V2 sensor was still enabled, but this was off and out of range at home.