Inertial dampener as in the sci-fi variety.
I’m think no. It would be too much of a mind fuck for me. I use those inertial forces to make judgement calls on a wide variety of things.
No? YES, YES, YES! First, I think of it as vehicle-wide complete gravity control. The following may be hard to imagine because we live every day in a world of “transmitted” forces.
You could not only survive a crash, but not even feel it. The force stopping your car (the acceleration and the rate of onset of acceleration) would be instantly applied to every molecule of your body. Hence, no death, no injury, no pain, not even discomfort. In fact, if the field extended to the exterior of the vehicle, there would be absolutely no damage to it, either.
Again, this is very difficult to imagine, because of the world we live in. Because forces are applied “piecemeal” we need, in worst case scenarios, seat belts and airbags, and even then we may get seriously bruised, or worse.
And, of course, one would be ethically bound to be careful of anyone in non-equipped vehicles, pedestrians, and so on. Unless you want to be a total dick. 
Given the safety advantages, definitely. Sure, you’d still be vulnerable to the car being outright crushed or debris smashing through a window, but that’s a lot less likely than injuries caused by being thrown around.
Is the car driver-less? If so, sure I’ll go for the inertial dampener package of options. Zzzzzzz.
To repeat myself, If we could manage a perfect artificial gravity, we may as well extend it to the entire vehicle, to the last molecule of the exterior. That would make the entire vehicle invulnerable in practice. Granted, a large enough force could send you flying for miles, with undesirable results, but that’s it.
No. That would remove a major source of input that is needed to safely operate an automobile. When you’re taking a turn, how do you know if you’re heading into it too fast? Because you can feel it. It would make driving a car too much like playing Forza Motorsport.
Isn’t an airbag a kind of inertial dampener?
Exactly! Think of it as an air bag! It only kicks in when acceleration rises to above a certain level. At that point, yes, please, I want one very badly!
Below that level, no: as noted above, acceleration informs the driver of driving conditions, and is also much of the fun of driving. Driving as if in a simulator (and not even a motion-replicating simulator, just a chair and a movie projector) would be a lot less fun than really getting out there and going up a winding country road.
Maybe the car drives itself, as suggested upthread. Okay, let’s assume not. You have a point, of course, but there are ways around it. The car could include a device which tells you just how much the i.d. is compensating for, and in which direction. Nor need such a device involve a readout. It could be analog in design, and transmit pressure to you in a way that mimics the prior driving experience.
I’m a lovably eccentric inventor in a superhero TV show. What do YOU think?
If the car has an inertial dampener, does it matter how fast you take that corner? If the car starts roll, the system just cuts down the sideways momentum until the car is stable again.
I’m not sure I follow. The physics of how the rubber meets the road is the same. The only way to stabilize the car would be to slow down.
I don’t think IDs work outside of the vehicle. (WRT to sci-fi tropes of course.)
Yes. I want to learn while driving upside-down.
I don’t think an inertial dampener would be needed or very useful for every day driving. But if there was one that only kicked in above a certain acceleration/deceleration threshold (like an airbag), then it would save many lives in car accidents.
So I voted “other”, but I guess I should have voted “yes”.
This is close to what I was thinking. I voted other as well.
I would want an inertial dampener in my car only as a safety device. I could see it being an “always on” device for transportation such as buses and trains, where it is less essential to feel those forces to control the vehicle.
Yes, I’d want one. It would be an excellent safety device, for the reasons already pointed out.
Also, if it actually worked by reducing inertia (as opposed to simply applying its own acceleration fields to alter momentum), it could have other benefits. For one thing, it would effectively give anyone in the active dampening field a form of super-speed, relative to the world outside the field, increasing the available reaction time in an accident.
The only way to make it not work outside the car would be to have an active system projecting outward that would counter the effects of the system that is projected inward. Otherwise, any change you made on the inside would have to affect anything on the outside.
And if you have those projectors, why not use them outside the vehicle, too?
I thought about this when I first saw a frog levitated by a magnetic field. I didn’t know it was such a common idea in Sci-Fi.
People who say you need inertia to corner - you’ll adapt. How did people lock car doors before remote locks? You mean they’d walk around the car and individually lock each door (and have to hold the external handle open when closing so the lock wouldn’t pop open)? How did people brake before ABS? In fact, how do you start a modern car if there’s no crank in the front?
Yes, of course, the safety effect would be too great to miss. One for pedestrians, too!
You have to be careful because when the dealer sells you the inertial dampener, he tries to sell it as part of a package that includes pyrotechnics in the steering wheel and console that blow up every time you get in a fender bender, and also undercoating.