I'm sitting in my patrol car right now (in a secured lot). I can't see how I could possibly swing one of these into my driver's side blind spot, which is a very likely avenue of approach for an ambush attempt on a parked patrol car. I'd be willing to learn if such a method exists, but I see zero way to either present it or have some semblance of aimed fire. I can, however, draw my pistol and fire aimed shots using as much of a Weaver stance as you can while seated. (Thanks @
Mas for that tip).
When I was doing robbery stakeouts and doing the McPhee "stuffed down next to the console" thing, my pistol is my counter-ambush tool. The rifle is still carried empty chamber, as stakeouts gone wrong become pursuits, and I don't want a free float firing pin equipped weapon that's not particularly well secured in the passenger compartment of my vehicle if I crash. Some folks think this concern is overblown, and they may be right, but I know what my department policy and my gut says.
Most of us aren't doing executive protection and, unless you're driving a marked car, are unlikely to be targeted for assassination. You are more likely to be carjacked. Imagine a gunman at your window with a gun on you. HTF do you get to your snubby shotgun and swing it to your driver's side window before getting shot? You can't. If you comply and get out of the car, where's your snubby shotgun? Inaccessible.
A handgun, though, especially carried strong side is right near where you're reaching for your seat belt release. Additionally, you can start compliance by opening the door and starting to get out, then complete the draw and fire on your attacker. It's worked pretty well in real life in multiple attempts. Anyone who wants to show me how this snubby shotgun is going to work better (or at all), I'm going to need to see the video.