My street impressions so far. This is not my track wheel and tire setup.
1. Grip, grip grip. I have so much confidence entering a turn regardless of the pavement conditions.
2. Car feels absolutely planted and solid.
3. The ride is better. Hitting expansion joints or sharp bumps is much less jarring. These tires seem to round off the edges of the sharp bumps. Keep in mind I have Recaro Sportster CS seats so I feel everything.
4. Very slight increase in tramlining on the freeway.
5. The road noise is lower.
6. The steering feel is basically unchanged. Maybe it is a bit heavier but can't say for sure.
To summarize, a great improvement over the stock ZCP wheels and tires.