I prefer a revolver as a car/truck gun; because when fired from inside the vehicle you don't have to contend with hot expended shell casings ricocheting around inside the vehicle.
If you are firing your weapon inside your vehicle. hot shell casings ricocheting around inside are the least of your concerns.
Besides incoming rounds the noise factor inside a car is enough to make you permanently deaf. Ear protection? Get a silencer? It's only a truck gun.
You're both right the way I see it!
It's true if inside a car shooting I would rather have my revolver like napp said, (up until the point I needed more than the 6 rounds it holds) I know what it's like to have a piece of brass tatoo ya!
And rockyfatcat is on the money too, I've shot from inside, never from inside a car, but inside of small rooms practicing clearing them. It's crazy loud. I wear hearing aids now, the noise will get ya too.
So a suppressed revolver should work fine!