300tdi timing cover dust seal

[Mercguy]

Does anyone ever replace the dust seal (crank) on the front timing cover when they do timing belt / fan pulley bearing?

Just asking, as I have a spare cover here, and new bearing. I was looking at the dust seal and thinking it might be worthwhile doing - but have no idea how long the service life is on them.

Anyone with experience - opinions welcome.

TIA.

[AK83]

both times I'd done the belt on mine, I used the kit form of the belt and associated parts. They include the dust seal in the kit, so may as well use it.