I am looking to purchase an air kit for my car. I was wondering whats the up/down side to having air cylinders. Also are the CCE Air System Cylinder Kits good? If you know of a good brand and or have personal experience with air bags/cylinders please give me a run down of your thoughts.

Don't get one! They suck. I said that cuz' I have one. You always have to adjust the pressure cuz' of the temperature (weather). When it gets hot the air expand(lower the pressure) and when it gets cold its dense(raise the pressure). You can't ride more than two people cuz' it will bottom out on you. It makes a squicking sound when your driving around. If you have too much pressure it feels like its going to pop. Its just for show and they are not reliable. I've changed my solinoid a couple of times already cuz' they leak alot.