With all four wheels spinning, you need to be pretty quick on the steering wheel - the 911 will move around laterally (uh, which means it'll dart around in search of a curb or an oncoming car.) Second gear comes almost instantaneously and with no interruption in power, then third, then fourth, then, oh, hello, Officer. Oh, and your passenger might pass out with fear. If not, he or she will likely be screaming at a pitch slightly higher than that of the police cruiser's siren.
If you really want to scare the daylights out of someone while retaining your license, you'll need a curvy race track. While it's certainly possible to frighten yourself and everyone around you on a curvy public road, that kind of fear is there for a reason. It's a healthy, self-preservation reason.
And besides, 911s aren't the kind of cars to take past their limits on narrow public roads. Their brilliance is how high the limits are, not how easy you can recover once you've blown through them.
On a racetrack, though, you can play with the Turbo in a controlled environment with lots of run off, and that invokes good fear. The Oh-My-God-this-car-isn't-going-to-make-this-curve kind of fear. Because if you know how to handle it, the 911 Turbo will, in fact, make the curve.
Nothing like the widow-maker 911s of yore, modern 911s nevertheless retain the rear-engine tendency towards lift-off oversteer. That feature may be a liability on the street (with stability control switched off), but it makes 911s fabulously throttle-adjustable on the track, and this Turbo is no exception. The last-generation Turbo was very, very fast around a race track, and it would happily powerslide around corner after corner. When you tried to be neat, tidy, and quick, though, it required serious effort: it would understeer on the way into a corner, and then when the boost hit (some measurable time after you squeezed the throttle), it would transition quickly into oversteer. Fun? Yes. Fast? Well, yes, but only if you really, really knew what you were doing. Like, if your name was Walter Röhrl. And more importantly, if you decided to enter a turn sideways - i.e. by lifting off at turn-in to rotate the back end - you had your work cut out for you to gather it back up.
The new Turbo is a lot more forgiving. The transitions between understeer and oversteer are softer, slower, and easier to manage. Thanks to the miserably damp conditions at Estoril, we only managed two laps behind the wheel ourselves, but Porsche did allow us some shotgun rides with their factory drivers.