"Almost all shifting problems I’ve ever had with the BBSxx have come from bent derailleur hangers or misaligned derailleurs. In my experience, a properly tuned and straight derailleur should not break chains even when shifting under load. Many people who use the BBSxx just tap their ebrakes when shifting under PAS which essentially does the exact same thing as the gearsensor.
What about with my fancy expensive IGH?
For an IGH it’s a totally different story. Many 3 speed IGHs like the Nexus 3 and the Sturmey Archer 3 speed hub seem to not complain too much when shifted under load. I have beaten the crap out of my 3 speed IGH’s and shifted them constantly under load without any issues. Other IGH like many more delicate 7 or 8 speed IGHs will absolutely self-destruct if they are shifted under the full 1500W load of a BBSHD, so a gear sensor would be absolutely mandatory in that instance."
In the end, the choice is yours of whether to go with the gear sensor. In all honestly, I could take it or leave it, $55 buys a lot of drugs beans and rice. My two E-Rad branded BBS02 drive units are my least used ebikes in my garage, and I seem to get by just fine without a gear sensor on my other 10 ebikes. If you’re an ebike fanatic and you don’t mind springing for the extra $50 it might be worthwhile for you. I’ve just gotten in the habit of not pedaling for two seconds when I want to shift, then shifting and then starting to pedal again. As the power slowly ramps back up your shift will be silky smooth and chain-crunching free.
