I have been running KW1, for the past 5 years, I have no issues with them. Like you stated they cannot be adjusted. Do I wish I have used the KW3, only now, but I am now tracking my Z a lot.
For what I do with tracking the Z, they feel great, for everyday driving, its a bit bumpy and if you lower the car too much, which you can, then you start having to think about speed bumps and dips.
I am sure, if you search the forum you can find good opinions and what other members have done and are using.
