The last time I took my 86 300E into the dealer they updated the airbag expiry sticker, from 1996 to 2001. Upon further inquiry, I was told that the effective life was first determined to be ten years, and recently extended to 15 (hence the update). I imagine the same guidelines extend to your vehicle, although I would be curious about the actual effective life of the SRS system (that is, not motivated by the manufacturer's fears of potential lawsuits, etc...). Apart from that issue, I would think that as long as your SRS warning light doesn't light up while driving (and that the bulb works!), your airbag should be ready for action, god forbid!