Oh, and if you still want to try a magnetless sensor and are worried about them falling off the hub or crank arm and losing them, you could try some cheap Magene sensors from Aliexpress, which are around $12 each. You could look around the forum for feedback about Magene. The newest version is the S3+, which supposedly has a new geomagnetic sensor, whatever it means. The old version found on Amazon is the Gemini 200 or 210. The only difference in appearance is the sticker on the back of the battery cap, so you would never know if it was the old model with a new label.