I have been wearing Hit-Air jackets from Mugen Denko in Japan for years. I have survived one 104 kph crash where there other two bikers wound up in hospital with all sorts broken - I had just a sprained ankle and thumb.
The airbag protected my neck, althought the helmet was scraped and the rest of me slid down the road on a cushion of air. The system uses a mechanical release which is more reliable than electronic gadgets. And it weighs no more than a normal jacket.