The ARBs make a big difference to stiffer setups as well. As you know, I went from the Racingline kit to much stiffer coilovers and even they benefitted from the addition of ARBs.
Uprated suspension transforms the car from factory. ARBs adds another cherry on top. Adjustable dampers puts yet another cherry on top, plus a healthy sprinkling of 100s and 1000s. Using all 3, you can fine tune the ride and cornering feel to compensate for the summer/winter durometer differences in the bushes and tyres
For example, over summer, I usually dial-in 2-3 clicks more damping to compensate for the soggier tyres and chassis bushes. It's especially noticeable in the top mounts and tyre side walls. Need to get some decent solid top mounts but the only decent ones are Ground Controls @ £450. Wish I'd kept my old ones now