I would give you 25 miles.

At 200mph, an ordinary car is inherently unstable, way beyond the rating of its tyres and the slightest bump, curve, stone or movement will see you off the road and into a ditch (and, at that speed, likely dead).

F1 only goes up to 233mph and that's on a regulated track with a BUNCH of technology keeping you on the road, ridiculously fast reactions from the driver, fingertip control of every aspect of the car (raising and lowering parts, changing braking balance, etc.), and the best drivers and car teams in the world, and they still spin out on straights sometimes.

In a commercially-available car? Not a chance. It's just not designed for that and at no point would an ordinary driver be able to guarantee they'll make the next mile (which you traverse in just 18 seconds at that speed).

I drove on the Autobahn once in a well-tested and excellent condition ordinary vehicle, at 3am, in the middle of nowhere, on a long straight, with literally not a car visible all the way to the horizon, and at 130mph, I decided to bug out. The car was shaking and rattling, the slightest movement of the wheel was amplified (twice the angle / response as at 70mph, if you think of it), my fingers were clamped onto the wheel, and it did not in any way feel safe.

At 200mph, you'll just die, straight or not. It doesn't matter who you are. Even a Formula 1 driver wouldn't do that in an ordinary vehicle. Just the sheer angles and forces at play mean you're effectively on a skidpan with the slightest rise of the road, wind gust or movement of the wheel. But a skidpan at a speed that you have literally no hope of recovering from - the slightest wobble and you'll cross all three lanes in a fraction of second.