The reason I was thinking cases is because I don't own enough guns to fill a closet. The biggest complaint my wife has with our current home is that we don't have enough closets, so me attempting to commandeer an entire closet won't go over well. And yes, I could just store linens and other stuff in there too, but I'm positive that family/company would have enough evidence to prove I'm insane when they find out I lock up my linens.
And this is the appeal of pelican cases (or other similar type cases) that can be sealed, locked and stored anywhere (perhaps even at the base of a closet). Putting an eye bolt into a stud and running a cable lock through it to the locked cases is sufficient to ensure they don't grow legs too easily.
eta: I considered a large job site box to store all firearms and all my ammo, which should be sufficiently heavy that it wouldn't walk off without a forklift, and frankly, who brings a forklift when they burglar someones home?The reason I avoided that is that they are still large/heavy/awkward to move by oneself although easier than a safe.