There is no doubt that ESP will add some time to those that have an idea of what they are doing, it really wasn't designed for them. The idea was to keep folks that only "think" they know what they are doing from destroying themselves and their car. That's why ( I think) it's a good idea for newbies to leave it on for a while on the track, to make it a little easier to learn what's going on before the stuff hits the fan... . Works good at autocross as well, keeps people from spinning out and embarrassing themselves. It's an excellent learning tool that can be at least partially turned off when you want to "play".
At VIR the Hog Pen is a 90+ mph turn, it has to be to get to 150 or so before heavy braking at the Horseshoe (much of it is up hill). The back straight is similar between Oak Tree and the Rollercoaster, except that you start out at about 30 to 35 mph and the entry to the Roller Coaster is blind. You have to rely on the flagman to know what's over the hill (This one starts as a down hill run and half way through goes uphill). We normally run the full 3.27 mile course. You may have see the course on TV they run the American LeMans series as well as other series there. It's a VERY fast course.
Summit Point is a bit slower, but 130 on the main straight into the hairpin isn't uncommon, the carousel is fun, but you have to hit turn 11 at least 70 mph in order to get any speed on the straight... Great course, and close enough to have fun at.

http://www.virclub.com/vir/index.php...=23&Itemid=106

http://www.summitpoint-raceway.com/