Lifetime of air suspension bags ?

maybe a maintenance ritual of hosing the bags while in extended mode?

I found grit higher up than accessible at maximum height although the holes were lower down at around off-road height where the rubber moves and would rub on any grit there at the time.

Seems that the shocks go soft well before the air bags reach end of life, i know will need replacing at some stage and its tempting to just replace the shock which may or may not be economical.

Air-springs for D3/D4 by themselves are quite expensive so don't get caught replacing shocks then have to buy air-springs.

I fitted after-market complete assemblies to my D4 then when the cheap shocks went soft in no time I fitted genuine shocks because I knew that the air-springs would still be in good condition.