New chassis bushes

To my opinion, the body feels always a bit jittering especially on bumpy roads. Did everyone replace the cushion bushes between chassis and body with upgraded or simply new ones?
I would like to give the car more torsional stiffness. Is it noticable or isn´t it worth the effort? Did someone even replace the cushions by solid Aluminium or Steel chunks?
What do you think about?

In my opinion,different shocks will make the biggest "feel" difference.

I replaced all the rubber body bushings on my 1994 Buick Roadmaster wagon 5 or 6 years ago. It made a pretty sizable difference in how the car rode. There are no real lower body bushing on the front 3 positions of the B body cars except for the 9C1 Police package cars. Even the SS didn't get lower bushings from the factory. Doing this gave the car a bit of a floating feeling. I used the 9C1 spec body bushings in most positions, but some in the rear are wagon specific so those were replaced with stock Buick stuff.

Do not use solid body bushings, you'll hate them almost right away.

Here's a link with more info on body bushings, and some upgrades:
http://www.impalassforum.com/vBulletin/17-suspension/255855-rubber-body-mount-bushing-question-suggestion.html

Refering to my service manual, the RM should have 7 body mount points at every side. Under the battery tray ( what has to be replaced usually   ) and opposite theres as well  cushion bushes which are not refered as "Body Mounts" from the manual, but they are fixpoints as well. A friend of mine who owns a Caprice told me that his car has no body mounts in the front, it might be sliding on the frame, just fixed at the rear and middle.
To my Information, Police car bushes aren´t available any more, but there´s some aftermarket poly bushes, do they work? Would it be possible to upgrade the car to the Police car layout ?

Just re-use rubber if yours are falling apart. The lower bushings described on theherd are available in rubber as reproductions on ebay.

I did the bushings on some previous roadmasters but it's been too long: I can't recall if it had the front 3 lower bushings or not. There is no #5 bushing, like on the G-body. I vaguely remember not being as impressed by the mod as I was when I did it on the caprice (which did not have the front bushings). It does make a difference though.

It used to be a cheaper mod to do. It's not that hard, but if you replace them, make sure you hit the bolt with pb blaster or liquid wrench. You don't want to spin one.

People on ISSF seem quite pleased with the new connecting brace. That should also improve the chassis stiffness. Have not tried it myself.