None of them are technically safes until you spend the equivalent to a car (I'm looking at you Graffunder ). The Stackons are just sheet metal cabinets with a shitty lock. Meets the requirements of keeping them under lock but can be opened with a big screwdriver and a hammer in less than a minute. I don't even believe the Winchester and other like it are even RSC rated. Once you get into the $1500+ you typically get one that is UL RSC listed (some of the AmSec and Browing). If you spend some true 1% $$$ you can get something that would truly be considered a safe and at that point you just get the safe door and have a built in vault/saferoom.
Regardless of what you get, spent the time and $ to bolt it to the floor, preferably on a concrete slab, with captive bolts that go all the way through the slab. If you can have it where the side opposite the hinge is against a wall as this eliminates using bodyweight on a prybar attack.