I've only worn Shoei's and Arai's - but I was shopping around for a new lid for this season. Looked at everything BUT an Arai - since I disagree with their sales policy, I will no longer buy their helmets.
I actually ordered a KBC Racer-1 (from HH, they don't have tinted shields for them btw) - when it arrived it was scratched up pretty good so I had to send it back. But, I got to try it on and I can honestly say I wasn't too impressed with them. As I said in another post, a lot of it had to do with the fit of the helmet - but I wasn't crazy about the shield system or the finish. Just my opinion.
In the end I've decided to try out a OGK FF3 - still waiting for it to be delivered but when it is I'll post my thoughts.