When I first started making holsters, it seemed that EVERYONE had an idea for a holster.
One of them was a "driving holster," and I thought about making one, but then I thought, WHO actually USES one ? I, and none of my gun friends even knew of someone that did.
As for the practicality, if you carry in a regular holster, why do you want to change your accustomed draw stroke for short periods of time ? Since most driving holsters are not concealable, everytime you stop for gas, you better remember to swap it back, or risk being reminded to do so when your nice, dent free gun falls to the pavement at the gas pump....
If you "carry" the gun in your car, why not KEEP it where it is ?
If your current holster isn't comfortable when driving, then I suggest changing to one that IS........but, that's just me !
Innovative Kydex Tactical Gear