Go with coilovers and a sway bar set-up all the way. You have several options available to you. A lot of it depends on how you drive your car. If you just want better cornering for everyday driving and would like a better looking stance, Don't be pressured to buy KW V2's. They'll be overkill and you'll spend too much. Now if you are looking to do road courses and more high performance driving, the KW V2's will be the way to go.
Your three main choices are KW, ST Suspensions, and Eibach as far as coilovers are concerned. Hotchkis and STSuspensions both make a quality set of sways. The sways alone make cornering a night and day difference with these cars.
Installation costs will vary from shop to shop. Could be anywhere from $300 to $600. But...if you are mechanically inclined, have a buddy to help and have the tools, you can honestly do the job yourself in 4-7 hours. (depends on beer/smoke break frequency).
I personally went with ST suspensions coilovers (same as KW V1's, performance wise) and Hotchkis sways. I LOVE the way the car sits and the way it handles is actually exciting. For a 4000+ lb car, I'm very surprised and satisfied.
If you have more questions about this matter, you can click the link in my sig and search around the site for your options/pricing/info. If you call Josh at HHP, he'll hook you up with some info and a good price for what you want. Hope that helps.
