Bilsteins are said (here as well) to be a noise free, comfortable and improved setup over stock. If I could do it all over again, I'd be tempted to go that route. That said, the Kw's are noisier when it's cold, but damn they're squeaky. My car is also pretty loud but when the roads are bumpy and cruising at low speed or going downhill, they sound like pogo sticks. During the day they are more manageable. I'd say go with Bilsteins for street, and KW for those who track their cars often.