S212 Front Suspension question

[Candellara]

We replaced all the front control arms on our E Class estate about 10,000 miles ago and the suspension top mounts and springs not long after, but the car has developed a clunk when travelling over potholes.

Not alot left to change but the ARB drop links were last done in 2018 - 30,000 miles ago. Do these wear out this quickly?

I also note that the car has never had any engine mounts changed and we're on 100k miles now. Is this a relatively easy swap out?