These people should maybe call a lawyer and ask if this is a good idea. The first person who dies because their safety equipment was disabled will generate a wrongful death lawsuit to the tune of a hundred million dollars.
this is even independent of the subscription thing. like if the thing needs a battery and the battery is dead, it needs to be extremely obvious it's not going to work. parachutes have this kind of problem but a reasonable skydiver has parachute training whereas a reasonable biker doesn't have airbag training.
- You need to turn it on when you're going to go ride.
- When you do that (in brief summary): You get a green LED if you're good to go, a red one if you're not, and if it's dead you get no LED, obviously.
- If you're in the no subscription state or it's otherwise not connecting to the app, you get two LEDs flashing red when you go to turn it on. You've got a 30 day grace period on the subscription expiration and it won't cut out out mid-ride even if that's when it hits the 30 day mark, just the next time you go to ride it'll give you the error instead of green.
- There's a battery light that comes on with 30% of battery left, which looks to be about 7 hours.
I would say that "when I hit the power button to go ride, I get a green LED if it's working as intended" is about as foolproof as is reasonably possible.
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I'm not a huge fan of the subscriptions for everything model, but IMO their policies are about as safe and reasonable as you could get for the product.
Vest (FAQ at bottom): https://www.klim.com/Ai-1-Airbag-Vest-3046-000
Manual for the inflator/controller(?): https://www.inemotion.com/en/support/user-manual-inbox/
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I'm also not a lawyer, but I'm not sure "I picked up a safety device I don't know how to use, didn't read the directions on how to use it, used it wrong, and it didn't protect me" is really the legal standard.
At risk of stating the obvious: There's a pretty much infinite number of ways you could improperly use any safety device and have them not work as intended, plenty of which "reasonable" people could think to do.
This is the flawed logic we deal with these days... :/