As Dan says above, I've had this done on my car. Was going to stick a review up in the thread a few weeks later but then the SJM trader section disappeared before I could.
I bought the car from a family member who was its original owner with 49K on the clock, and I had now taken it up to 64K. The handling was by no means 'bad', but it just didn't really feel completely all there. Tired would be a good summary. It was 'Acceptable, but could do better'. On about 54K the front left spring snapped so I replaced the pair with another set of used Cup springs. Then in the last couple of months before having the suspension refreshed it started to feel like the rear shocks had gone as I would hit a bump and the rear would try to introduce me to the nearest hedge… but I'd rather not get acquainted with the hedge!
So then in September I took it to Dan@SJM for a complete refresh and a set of Cooksport Springs. Dan was great to deal with, but the important bit is how's it handling now? Just brilliant. I can really see why all the magazines at the time raved about the handling being so sharp on these. I never drove the car when it was new, but to me now it really does feel like a new car and has got its edge back. The best one word description I could come up with is "Go-Kart", as it really feels like one now!
It copes with bumps so much better and so it looks like my date with Mr.Hedge has been cancelled. In cornering you can feel the ARB working more to keep it flat, and the speed it can carry into a corner is simply phenomenal. It was certainly not an understeery mess before or anything, but it can now corner a good bit quicker than it used to.
I'll admit that it's a decent amount of cash, but I'd say it's totally worth it. To quote Evo magazine when they reviewed the 182 back in 2004: "In fact, so good is the Clio 182 with the Cup chassis set-up that I feel moved to make a bold statement - I think it's the best hot hatch ever built."