Lee fitted "M" rubber lollipop bushes to my Z3 3.0 ..They are the ones as per your photo with some cut outs but not as many holes as standard and not totally solid ..Doing that, replacing the shocks and the rear beam bushes on the subframe transformed a car that was pretty horrible to drive when I bought it to something that resembles a sure footed Go Kart!
I'm convinced that so many people are driving around in Z3s with totally shagged suspension but yet good enough for the MOT that its contributed to many people viewing them unfavourably..