Rantingredneck, I read this entire thread and I see that you have been agonizing over this decision for more than three months now. I might as well throw my $0.02 out there for you. Hey, us gun nuts need to counsel each other, right?
I carry a J frame S&W 340 PD in .357 magnum most of the time and I generally don't like to leave a gun in the truck but I will do it from time to time depending on the situation. I mounted a small safe in my truck and secured it to the vehicle body with bolts. However, if I am out hunting, scouting or just knocking around the woods, a 6" GP-100 or 6" Taurus model 66 will be in the truck as a sidearm. If I want to leave a gun in the truck, the Taurus gets left in the truck safe along with a belt holster because it has the least monetary value although it is a solid performer and both are built from stainless steel.
I never did like leaving a long gun in the truck because in the event I need to leave the truck somewhere, the long gun is harder to hide and I can't very well conceal it while walking. The Marlin 1894C is an excellent compliment to the .357 revolver while spending time in the woods and I have plans to acquire one very soon. Congratulations on your acquisition. I can say without fear of contradiction that my 6" .357 revolver shoots just like a rifle and out to 50 yards, I can hit anything with that revolver that I can hit with a rifle. If you have a 6" .357, that is a rifle for all practical purposes, in my opinion. The game that I have killed with my 6" gun is just as dead as the game I shot with my .30-30 and they don't know the difference.
Four 6-round speed strips, two 5-round speed loaders and two 6-round speed loaders are in my vehicle at all times. All this ammo is .38 special so it can be used in any revolver. The revolver itself has .357 ammo in its chambers. In addition, I have two 8-round speed strips stored with .357 magnum rounds. This makes it easy to spot the .357 ammo and there is no danger of confusing it with .38 special when I'm in a hurry.
So, at any given time, there is plenty of ammo stored in my vehicle but no unsecured gun for the smash-and-grab guys to get.
I'm a big fan of the .38 special/.357 magnum setup. If it is ever necessary for me to fire from within the vehicle, I will do it with my .38 special so myself and my occupants are spared the ear-splitting shock waves. On the other hand, I don't want more guns in the vehicle than I can quickly pack up and carry with me in the event of a vehicle breakdown or other emergency. Hey, even a new truck can have a breakdown and you don't want the tow truck guy or the dealership guys to steal your guns. Keep it simple.
I would tend to prefer high capacity weapons at home for HD. It is not unusual for break-ins to be done by teams of three or four guys. That's where it makes sense to have a high capacity gun or two guns handy. In the outdoors, I think my greatest threat could come from a pack of coyotes. In that case, I think my six shooter will be enough. At least, I will shoot the alpha coyote first and work my way down until the others give up and leave me alone. A carjacker is likely to be a lone crackhead or maybe a team of two. That's the way it seems to be happening around here anyway. I just try to keep everything as simple as possible. One platform for the road and another one for the home.
would be rough but!!!! at the minimum you have one there if necessary!