The more difference you can feel just goes to show how much they are needed.
I have them on my cos and had on my few mk3/4's.
All were polybushed everywhere but one of the most benefits I found was under heavy braking on bad surfaces the car did not try and wander all over the place, helped car stay flatter too, and made ride a tiny bit harsher, but well worth it as car at all times was vastly more stable.
tabetha