A few of my suspension bushes look split and wondered if anyone has ever fitted poly bushes instead of standard ones and if you have did it make the ride harsh? I have a 20 ton shop press to swap them over. Thanks Kev.

you haven't said which bushes?

There aren’t too many which would poly bush, personally wouldn’t bother. It’s not a sports car or a hardcore off road machine....

The big bush on the upper arm is not attached on all sides to allow for articulation, so poly bushing that would not really be a good idea?

Some times it’s easier to swap while arms with bushes in rather than individual bushes, but on the other hand if you have a 20t press then that makes life a lot simpler. There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial

I had a quick look under the front of the car and thought the rear lower arm bush looked rotted. I've read that this seems to need replacing quite often? Just thought I'd look at something more durable if that's the case but didn't want the ride to feel harsh. I'm still learning about this car and if standard bushes last OK that's the way I'll go. Some times when I brake hard I can hear a slight 'thunk'. Thanks Kev.

The outer lower rear arm bush is a rose joint so again not really one you would want to poly. Inners possibly.

The Lemforder or Delphi versions of the joints which are the oEM ones last reasonably well.👍🏻

If you get a thunk under braking check your pads first. They can move slightly in the caliper giving a slight thunk, especially with the Brembos. There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial