I am running King superlow springs and Koni adjustables. It has had the most effect on the overall performance of the car more than anything so far. A vast, vast improvement over stock.
As for how I have found them, in terms of practicality, well in short, very good. Yes my car is rather low, but if you take your time with tricky steep approaches / exits, and give it some angle (hey Kell...) , then there are generally no worries. The things that give me the most trouble are speed bumps at the top of a steep slope, like in Castle Hill carpark. As the car goes over the verge, the combination of longish wheelbase, low front, and speed bump on the verge can conspire to a scrape or two, but to date most have only been on the chassis rails. Undercarriage damage has been very very limited so far.
I have bottomed out occasionally, but only when there's been a bit of a load in the car and I've hit a fairly impressive dip with some kph.
But all in all, if you are careful around carparks and steep approaches/exits, the superlows are no trouble. And the stance with them is just plain pants-splitting! :s6: