About the wheels... Rotating mass is rotating mass... no matter if it is at the flywheel or wheels. OK, it has a rear-end reduction, but you also have to stop that rotating mass (brakes). So, do yourself a favor and buy the Kiesers. I used to be a dealer... and I might still be so I'll call them tomorrow and I'll let you know.
Also, if it is allowed, go buy the softest slicks you can buy... I suggest 230 compound Goodyears. If you are running on 10 year old slicks, the "skinny winney" Khumo's are probably even better. Another thing to remember, most slicks including Goodyear 430 compound take about 3 laps on a road race course to "come in"... get enough temperature in them to really work. "DOT race radials" like the Hoosiers or Kumos "come in" much quicker than slicks. So, for autocross, you might get better times with "DOT race radials"... or go to tire warmers for the slicks. (I say "DOT race radials" because these are really race tires that have the tread stenseled on and have DOT approval... barely.)
There was another question about where I race, and is it social. I race in the South West and don't normally make it above Sears Point. Social??? Well, it depends. At nationals NO... NO... NO. I'm there to win. The competition is too tough to be very social. Any time between practice, qualifying, and the race is spent on the car. At regionals, when I'm in the car, it's still NO... cause I'm there to win too. BUT, most of the rest of the race day, it's pretty social.